RenderView::compositor() should return a reference.

<https://webkit.org/b/120217>

Reviewed by Beth Dakin.

The RenderLayerCompositor is lazily constructed by compositor() and never returns null.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@154504 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

+2013-08-23  Andreas Kling  <akling@apple.com>
+
+        RenderView::compositor() should return a reference.
+        <https://webkit.org/b/120217>
+
+        Reviewed by Beth Dakin.
+
+        The RenderLayerCompositor is lazily constructed by compositor() and never returns null.
+
 2013-08-23  Yoav Weiss  <yoav@yoav.ws>
         Fix srcset's image candidate algorithm when DPR exceeds all candidates

Source/WebCore/css/MediaQueryEvaluator.cpp

@@ -570,7 +570,7 @@ static bool transform_3dMediaFeatureEval(CSSValue* value, RenderStyle*, Frame* f
     bool threeDEnabled = false;
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* view = frame->contentRenderer())
-        threeDEnabled = view->compositor()->canRender3DTransforms();
+        threeDEnabled = view->compositor().canRender3DTransforms();
 #endif
 
     returnValueIfNoParameter = threeDEnabled;

Source/WebCore/dom/Document.cpp

@@ -4842,7 +4842,7 @@ void Document::windowScreenDidChange(PlatformDisplayID displayID)
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* view = renderView()) {
         if (view->usesCompositing())
-            view->compositor()->windowScreenDidChange(displayID);
+            view->compositor().windowScreenDidChange(displayID);
     }
 #endif
 }

Source/WebCore/html/HTMLMediaElement.cpp

@@ -3799,7 +3799,7 @@ bool HTMLMediaElement::mediaPlayerRenderingCanBeAccelerated(MediaPlayer*)
 {
     if (renderer() && renderer()->isVideo()) {
         ASSERT(renderer()->view());
-        return renderer()->view()->compositor()->canAccelerateVideoRendering(toRenderVideo(renderer()));
+        return renderer()->view()->compositor().canAccelerateVideoRendering(toRenderVideo(renderer()));
     }
     return false;
 }

Source/WebCore/page/Frame.cpp

@@ -864,7 +864,7 @@ String Frame::layerTreeAsText(LayerTreeFlags flags) const
     if (!contentRenderer())
         return String();
 
-    return contentRenderer()->compositor()->layerTreeAsText(flags);
+    return contentRenderer()->compositor().layerTreeAsText(flags);
 #else
     UNUSED_PARAM(flags);
     return String();
@@ -991,9 +991,8 @@ void Frame::deviceOrPageScaleFactorChanged()
     for (RefPtr<Frame> child = tree()->firstChild(); child; child = child->tree()->nextSibling())
         child->deviceOrPageScaleFactorChanged();
 
-    RenderView* root = contentRenderer();
-    if (root && root->compositor())
-        root->compositor()->deviceOrPageScaleFactorChanged();
+    if (RenderView* root = contentRenderer())
+        root->compositor().deviceOrPageScaleFactorChanged();
 }
 #endif
 void Frame::notifyChromeClientWheelEventHandlerCountChanged() const

Source/WebCore/page/FrameView.cpp

@@ -462,7 +462,7 @@ void FrameView::setFrameRect(const IntRect& newRect)
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
-            renderView->compositor()->frameViewDidChangeSize();
+            renderView->compositor().frameViewDidChangeSize();
     }
 #endif
 
@@ -749,9 +749,10 @@ void FrameView::updateCompositingLayersAfterStyleChange()
     if (m_doingPreLayoutStyleUpdate || layoutPending() || renderView->needsLayout())
         return;
 
+    RenderLayerCompositor& compositor = renderView->compositor();
     // This call will make sure the cached hasAcceleratedCompositing is updated from the pref
-    renderView->compositor()->cacheAcceleratedCompositingFlags();
-    renderView->compositor()->updateCompositingLayers(CompositingUpdateAfterStyleChange);
+    compositor.cacheAcceleratedCompositingFlags();
+    compositor.updateCompositingLayers(CompositingUpdateAfterStyleChange);
 }
 
 void FrameView::updateCompositingLayersAfterLayout()
@@ -761,8 +762,8 @@ void FrameView::updateCompositingLayersAfterLayout()
         return;
 
     // This call will make sure the cached hasAcceleratedCompositing is updated from the pref
-    renderView->compositor()->cacheAcceleratedCompositingFlags();
-    renderView->compositor()->updateCompositingLayers(CompositingUpdateAfterLayout);
+    renderView->compositor().cacheAcceleratedCompositingFlags();
+    renderView->compositor().updateCompositingLayers(CompositingUpdateAfterLayout);
 }
 
 void FrameView::clearBackingStores()
@@ -771,10 +772,10 @@ void FrameView::clearBackingStores()
     if (!renderView)
         return;
 
-    RenderLayerCompositor* compositor = renderView->compositor();
-    ASSERT(compositor->inCompositingMode());
-    compositor->enableCompositingMode(false);
-    compositor->clearBackingForAllLayers();
+    RenderLayerCompositor& compositor = renderView->compositor();
+    ASSERT(compositor.inCompositingMode());
+    compositor.enableCompositingMode(false);
+    compositor.clearBackingForAllLayers();
 }
 
 void FrameView::restoreBackingStores()
@@ -783,9 +784,9 @@ void FrameView::restoreBackingStores()
     if (!renderView)
         return;
 
-    RenderLayerCompositor* compositor = renderView->compositor();
-    compositor->enableCompositingMode(true);
-    compositor->updateCompositingLayers(CompositingUpdateAfterLayout);
+    RenderLayerCompositor& compositor = renderView->compositor();
+    compositor.enableCompositingMode(true);
+    compositor.updateCompositingLayers(CompositingUpdateAfterLayout);
 }
 
 bool FrameView::usesCompositedScrolling() const
@@ -794,7 +795,7 @@ bool FrameView::usesCompositedScrolling() const
     if (!renderView)
         return false;
     if (frame().settings().compositedScrollingForFramesEnabled())
-        return renderView->compositor()->inForcedCompositingMode();
+        return renderView->compositor().inForcedCompositingMode();
     return false;
 }
 
@@ -803,7 +804,7 @@ GraphicsLayer* FrameView::layerForScrolling() const
     RenderView* renderView = this->renderView();
     if (!renderView)
         return 0;
-    return renderView->compositor()->scrollLayer();
+    return renderView->compositor().scrollLayer();
 }
 
 GraphicsLayer* FrameView::layerForHorizontalScrollbar() const
@@ -811,7 +812,7 @@ GraphicsLayer* FrameView::layerForHorizontalScrollbar() const
     RenderView* renderView = this->renderView();
     if (!renderView)
         return 0;
-    return renderView->compositor()->layerForHorizontalScrollbar();
+    return renderView->compositor().layerForHorizontalScrollbar();
 }
 
 GraphicsLayer* FrameView::layerForVerticalScrollbar() const
@@ -819,7 +820,7 @@ GraphicsLayer* FrameView::layerForVerticalScrollbar() const
     RenderView* renderView = this->renderView();
     if (!renderView)
         return 0;
-    return renderView->compositor()->layerForVerticalScrollbar();
+    return renderView->compositor().layerForVerticalScrollbar();
 }
 
 GraphicsLayer* FrameView::layerForScrollCorner() const
@@ -827,7 +828,7 @@ GraphicsLayer* FrameView::layerForScrollCorner() const
     RenderView* renderView = this->renderView();
     if (!renderView)
         return 0;
-    return renderView->compositor()->layerForScrollCorner();
+    return renderView->compositor().layerForScrollCorner();
 }
 
 TiledBacking* FrameView::tiledBacking()
@@ -862,7 +863,7 @@ GraphicsLayer* FrameView::layerForOverhangAreas() const
     RenderView* renderView = this->renderView();
     if (!renderView)
         return 0;
-    return renderView->compositor()->layerForOverhangAreas();
+    return renderView->compositor().layerForOverhangAreas();
 }
 
 GraphicsLayer* FrameView::setWantsLayerForTopOverHangArea(bool wantsLayer) const
@@ -871,7 +872,7 @@ GraphicsLayer* FrameView::setWantsLayerForTopOverHangArea(bool wantsLayer) const
     if (!renderView)
         return 0;
 
-    return renderView->compositor()->updateLayerForTopOverhangArea(wantsLayer);
+    return renderView->compositor().updateLayerForTopOverhangArea(wantsLayer);
 }
 
 GraphicsLayer* FrameView::setWantsLayerForBottomOverHangArea(bool wantsLayer) const
@@ -880,7 +881,7 @@ GraphicsLayer* FrameView::setWantsLayerForBottomOverHangArea(bool wantsLayer) co
     if (!renderView)
         return 0;
 
-    return renderView->compositor()->updateLayerForBottomOverhangArea(wantsLayer);
+    return renderView->compositor().updateLayerForBottomOverhangArea(wantsLayer);
 }
 
 #endif // ENABLE(RUBBER_BANDING)
@@ -909,7 +910,7 @@ bool FrameView::flushCompositingStateForThisFrame(Frame* rootFrameForFlush)
     // visible flash to occur. Instead, stop the deferred repaint timer and repaint immediately.
     flushDeferredRepaints();
 
-    renderView->compositor()->flushPendingLayerChanges(rootFrameForFlush == &frame());
+    renderView->compositor().flushPendingLayerChanges(rootFrameForFlush == &frame());
 
     return true;
 }
@@ -946,7 +947,7 @@ bool FrameView::hasCompositedContent() const
 {
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView())
-        return renderView->compositor()->inCompositingMode();
+        return renderView->compositor().inCompositingMode();
 #endif
     return false;
 }
@@ -956,8 +957,7 @@ bool FrameView::hasCompositedContentIncludingDescendants() const
 #if USE(ACCELERATED_COMPOSITING)
     for (Frame* frame = m_frame.get(); frame; frame = frame->tree()->traverseNext(m_frame.get())) {
         RenderView* renderView = frame->contentRenderer();
-        RenderLayerCompositor* compositor = renderView ? renderView->compositor() : 0;
-        if (compositor) {
+        if (RenderLayerCompositor* compositor = renderView ? &renderView->compositor() : 0) {
             if (compositor->inCompositingMode())
                 return true;
 
@@ -987,9 +987,9 @@ void FrameView::enterCompositingMode()
 {
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView()) {
-        renderView->compositor()->enableCompositingMode();
+        renderView->compositor().enableCompositingMode();
         if (!needsLayout())
-            renderView->compositor()->scheduleCompositingLayerUpdate();
+            renderView->compositor().scheduleCompositingLayerUpdate();
     }
 #endif
 }
@@ -1026,7 +1026,7 @@ bool FrameView::isSoftwareRenderable() const
 {
 #if USE(ACCELERATED_COMPOSITING)
     RenderView* renderView = this->renderView();
-    return !renderView || !renderView->compositor()->has3DContent();
+    return !renderView || !renderView->compositor().has3DContent();
 #else
     return true;
 #endif
@@ -1782,9 +1782,9 @@ void FrameView::setIsOverlapped(bool isOverlapped)
         // a layer update in the parent document.
         if (Frame* parentFrame = frame().tree()->parent()) {
             if (RenderView* parentView = parentFrame->contentRenderer()) {
-                RenderLayerCompositor* compositor = parentView->compositor();
-                compositor->setCompositingLayersNeedRebuild();
-                compositor->scheduleCompositingLayerUpdate();
+                RenderLayerCompositor& compositor = parentView->compositor();
+                compositor.setCompositingLayersNeedRebuild();
+                compositor.scheduleCompositingLayerUpdate();
             }
         }
 
@@ -1793,9 +1793,9 @@ void FrameView::setIsOverlapped(bool isOverlapped)
             // since a frame uses compositing if any ancestor is compositing.
             for (Frame* frame = m_frame.get(); frame; frame = frame->tree()->traverseNext(m_frame.get())) {
                 if (RenderView* view = frame->contentRenderer()) {
-                    RenderLayerCompositor* compositor = view->compositor();
-                    compositor->setCompositingLayersNeedRebuild();
-                    compositor->scheduleCompositingLayerUpdate();
+                    RenderLayerCompositor& compositor = view->compositor();
+                    compositor.setCompositingLayersNeedRebuild();
+                    compositor.scheduleCompositingLayerUpdate();
                 }
             }
         }
@@ -1986,7 +1986,7 @@ void FrameView::scrollPositionChanged()
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
-            renderView->compositor()->frameViewDidScroll();
+            renderView->compositor().frameViewDidScroll();
     }
 #endif
 }
@@ -2041,7 +2041,7 @@ void FrameView::updateFixedElementsAfterScrolling()
 
     if (m_nestedLayoutCount <= 1 && hasViewportConstrainedObjects()) {
         if (RenderView* renderView = this->renderView())
-            renderView->compositor()->updateCompositingLayers(CompositingUpdateOnScroll);
+            renderView->compositor().updateCompositingLayers(CompositingUpdateOnScroll);
     }
 #endif
 }
@@ -2182,7 +2182,7 @@ void FrameView::visibleContentsResized()
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
-            renderView->compositor()->frameViewDidChangeSize();
+            renderView->compositor().frameViewDidChangeSize();
     }
 #endif
 }
@@ -2314,7 +2314,7 @@ void FrameView::resetDeferredRepaintDelay()
     }
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* view = renderView())
-        view->compositor()->disableLayerFlushThrottlingTemporarilyForInteraction();
+        view->compositor().disableLayerFlushThrottlingTemporarilyForInteraction();
 #endif
 }
 
@@ -2349,7 +2349,7 @@ void FrameView::updateLayerFlushThrottlingInAllFrames()
     bool isMainLoadProgressing = frame().page()->progress().isMainLoadProgressing();
     for (Frame* frame = m_frame.get(); frame; frame = frame->tree()->traverseNext(m_frame.get())) {
         if (RenderView* renderView = frame->contentRenderer())
-            renderView->compositor()->setLayerFlushThrottlingEnabled(isMainLoadProgressing);
+            renderView->compositor().setLayerFlushThrottlingEnabled(isMainLoadProgressing);
     }
 #endif
 }
@@ -2774,7 +2774,7 @@ void FrameView::performPostLayoutTasks()
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
-            renderView->compositor()->frameViewDidLayout();
+            renderView->compositor().frameViewDidLayout();
     }
 #endif
 
@@ -4020,7 +4020,7 @@ void FrameView::setTracksRepaints(bool trackRepaints)
 #if USE(ACCELERATED_COMPOSITING)
     for (Frame* frame = m_frame->tree()->top(); frame; frame = frame->tree()->traverseNext()) {
         if (RenderView* renderView = frame->contentRenderer())
-            renderView->compositor()->setTracksRepaints(trackRepaints);
+            renderView->compositor().setTracksRepaints(trackRepaints);
     }
 #endif
 
@@ -4033,7 +4033,7 @@ void FrameView::resetTrackedRepaints()
     m_trackedRepaintRects.clear();
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = this->renderView())
-        renderView->compositor()->resetTrackedRepaintRects();
+        renderView->compositor().resetTrackedRepaintRects();
 #endif
 }
 

Source/WebCore/page/Page.cpp

@@ -1323,7 +1323,7 @@ void Page::addHeaderWithHeight(int headerHeight)
         return;
 
     frameView->setHeaderHeight(m_headerHeight);
-    renderView->compositor()->updateLayerForHeader(m_headerHeight);
+    renderView->compositor().updateLayerForHeader(m_headerHeight);
 }
 
 void Page::addFooterWithHeight(int footerHeight)
@@ -1339,7 +1339,7 @@ void Page::addFooterWithHeight(int footerHeight)
         return;
 
     frameView->setFooterHeight(m_footerHeight);
-    renderView->compositor()->updateLayerForFooter(m_footerHeight);
+    renderView->compositor().updateLayerForFooter(m_footerHeight);
 }
 #endif
 

Source/WebCore/page/scrolling/ScrollingCoordinator.cpp

@@ -294,7 +294,7 @@ GraphicsLayer* ScrollingCoordinator::scrollLayerForFrameView(FrameView* frameVie
 {
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = frameView->frame().contentRenderer())
-        return renderView->compositor()->scrollLayer();
+        return renderView->compositor().scrollLayer();
     return 0;
 #else
     UNUSED_PARAM(frameView);
@@ -306,7 +306,7 @@ GraphicsLayer* ScrollingCoordinator::headerLayerForFrameView(FrameView* frameVie
 {
 #if USE(ACCELERATED_COMPOSITING) && ENABLE(RUBBER_BANDING)
     if (RenderView* renderView = frameView->frame().contentRenderer())
-        renderView->compositor()->headerLayer();
+        renderView->compositor().headerLayer();
     return 0;
 #else
     UNUSED_PARAM(frameView);
@@ -318,7 +318,7 @@ GraphicsLayer* ScrollingCoordinator::footerLayerForFrameView(FrameView* frameVie
 {
 #if USE(ACCELERATED_COMPOSITING) && ENABLE(RUBBER_BANDING)
     if (RenderView* renderView = frameView->frame().contentRenderer())
-        return renderView->compositor()->footerLayer();
+        return renderView->compositor().footerLayer();
     return 0;
 #else
     UNUSED_PARAM(frameView);
@@ -330,7 +330,7 @@ GraphicsLayer* ScrollingCoordinator::counterScrollingLayerForFrameView(FrameView
 {
 #if USE(ACCELERATED_COMPOSITING)
     if (RenderView* renderView = frameView->frame().contentRenderer())
-        return renderView->compositor()->fixedRootBackgroundLayer();
+        return renderView->compositor().fixedRootBackgroundLayer();
     return 0;
 #else
     UNUSED_PARAM(frameView);

Source/WebCore/rendering/RenderBox.cpp

@@ -275,7 +275,7 @@ void RenderBox::styleWillChange(StyleDifference diff, const RenderStyle* newStyl
             view()->repaintRootContents();
 #if USE(ACCELERATED_COMPOSITING)
             if (oldStyle->hasEntirelyFixedBackground() != newStyle->hasEntirelyFixedBackground())
-                view()->compositor()->rootFixedBackgroundsChanged();
+                view()->compositor().rootFixedBackgroundsChanged();
 #endif
         }
         

Source/WebCore/rendering/RenderBoxModelObject.cpp

@@ -289,7 +289,7 @@ void RenderBoxModelObject::contentChanged(ContentChangeType changeType)
 
 bool RenderBoxModelObject::hasAcceleratedCompositing() const
 {
-    return view()->compositor()->hasAcceleratedCompositing();
+    return view()->compositor().hasAcceleratedCompositing();
 }
 
 bool RenderBoxModelObject::startTransition(double timeOffset, CSSPropertyID propertyId, const RenderStyle* fromStyle, const RenderStyle* toStyle)

Source/WebCore/rendering/RenderLayer.cpp

@@ -312,7 +312,7 @@ RenderLayerCompositor* RenderLayer::compositor() const
 {
     if (!renderer()->view())
         return 0;
-    return renderer()->view()->compositor();
+    return &renderer()->view()->compositor();
 }
 
 void RenderLayer::contentChanged(ContentChangeType changeType)

Source/WebCore/rendering/RenderLayerCompositor.cpp

@@ -464,7 +464,7 @@ void RenderLayerCompositor::layerTiledBackingUsageChanged(const GraphicsLayer*,
 RenderLayerCompositor* RenderLayerCompositor::enclosingCompositorFlushingLayers() const
 {
     for (Frame* frame = &m_renderView.frameView().frame(); frame; frame = frame->tree()->parent()) {
-        RenderLayerCompositor* compositor = frame->contentRenderer() ? frame->contentRenderer()->compositor() : 0;
+        RenderLayerCompositor* compositor = frame->contentRenderer() ? &frame->contentRenderer()->compositor() : 0;
         if (compositor->isFlushingLayers())
             return compositor;
     }
@@ -1414,7 +1414,7 @@ RenderLayerCompositor* RenderLayerCompositor::frameContentsCompositor(RenderPart
     HTMLFrameOwnerElement* element = toFrameOwnerElement(renderer->node());
     if (Document* contentDocument = element->contentDocument()) {
         if (RenderView* view = contentDocument->renderView())
-            return view->compositor();
+            return &view->compositor();
     }
     return 0;
 }

Source/WebCore/rendering/RenderObject.cpp

@@ -1972,7 +1972,7 @@ void RenderObject::styleWillChange(StyleDifference diff, const RenderStyle* newS
 #if USE(ACCELERATED_COMPOSITING)
     bool drawsRootBackground = isRoot() || (isBody() && !rendererHasBackground(document()->documentElement()->renderer()));
     if (drawsRootBackground && repaintFixedBackgroundsOnScroll) {
-        if (view()->compositor()->supportsFixedRootBackgroundCompositing()) {
+        if (view()->compositor().supportsFixedRootBackgroundCompositing()) {
             if (newStyleSlowScroll && newStyle->hasEntirelyFixedBackground())
                 newStyleSlowScroll = false;
 

Source/WebCore/rendering/RenderView.cpp

@@ -584,9 +584,10 @@ void RenderView::repaintRectangleInViewAndCompositedLayers(const LayoutRect& ur,
     repaintViewRectangle(ur, immediate);
     
 #if USE(ACCELERATED_COMPOSITING)
-    if (compositor()->inCompositingMode()) {
+    RenderLayerCompositor& compositor = this->compositor();
+    if (compositor.inCompositingMode()) {
         IntRect repaintRect = pixelSnappedIntRect(ur);
-        compositor()->repaintCompositedLayers(&repaintRect);
+        compositor.repaintCompositedLayers(&repaintRect);
     }
 #endif
 }
@@ -595,8 +596,9 @@ void RenderView::repaintViewAndCompositedLayers()
 {
     repaintRootContents();
 #if USE(ACCELERATED_COMPOSITING)
-    if (compositor()->inCompositingMode())
-        compositor()->repaintCompositedLayers();
+    RenderLayerCompositor& compositor = this->compositor();
+    if (compositor.inCompositingMode())
+        compositor.repaintCompositedLayers();
 #endif
 }
 
@@ -731,7 +733,7 @@ void RenderView::setMaximalOutlineSize(int o)
         m_maximalOutlineSize = o;
 
         // maximalOutlineSize affects compositing layer dimensions.
-        compositor()->setCompositingLayersNeedRebuild();    // FIXME: this really just needs to be a geometry update.
+        compositor().setCompositingLayersNeedRebuild();    // FIXME: this really just needs to be a geometry update.
     }
 }
 #endif
@@ -1133,12 +1135,12 @@ bool RenderView::usesCompositing() const
     return m_compositor && m_compositor->inCompositingMode();
 }
 
-RenderLayerCompositor* RenderView::compositor()
+RenderLayerCompositor& RenderView::compositor()
 {
     if (!m_compositor)
         m_compositor = adoptPtr(new RenderLayerCompositor(*this));
 
-    return m_compositor.get();
+    return *m_compositor;
 }
 #endif
 

Source/WebCore/rendering/RenderView.h

@@ -190,7 +190,7 @@ public:
     void setIsInWindow(bool);
 
 #if USE(ACCELERATED_COMPOSITING)
-    RenderLayerCompositor* compositor();
+    RenderLayerCompositor& compositor();
     bool usesCompositing() const;
 #endif