[chromium] Support RTL pages and elements in the compositor

https://bugs.webkit.org/show_bug.cgi?id=56591

Reviewed by James Robinson.

Source/WebKit/chromium:

As the noncomposited content host layer is created and managed by the
Chromium compositor, adjust its transform appropriately in the layer
tree and at paint time to handle the offset required due to the
initial containing block of RTL pages.

* src/ChromeClientImpl.cpp:
(WebKit::ChromeClientImpl::allowedCompositingTriggers):
* src/NonCompositedContentHost.cpp:
(WebKit::NonCompositedContentHost::setViewport):
(WebKit::NonCompositedContentHost::paintContents):
* src/NonCompositedContentHost.h:
* src/WebViewImpl.cpp:
(WebKit::WebViewImpl::updateLayerTreeViewport):

LayoutTests:

Re-enable RTL tests for Chromium.

* platform/chromium/test_expectations.txt:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@103968 268f45cc-cd09-0410-ab3c-d52691b4dbfc

LayoutTests/ChangeLog

+2012-01-03  Adrienne Walker  <enne@google.com>
+
+        [chromium] Support RTL pages and elements in the compositor
+        https://bugs.webkit.org/show_bug.cgi?id=56591
+
+        Reviewed by James Robinson.
+
+        Re-enable RTL tests for Chromium.
+
+        * platform/chromium/test_expectations.txt:
+
 2012-01-03  Gavin Barraclough  <barraclough@apple.com>
 
         https://bugs.webkit.org/show_bug.cgi?id=75429

LayoutTests/platform/chromium/test_expectations.txt

@@ -3299,15 +3299,6 @@ BUGWK62754 SLOW LINUX MAC DEBUG : http/tests/misc/object-embedding-svg-delayed-s
 // Has been flaky/crashy for a while
 BUGCR86359 WIN : fast/dom/DeviceOrientation/add-listener-from-callback.html = PASS CRASH
 
-// Broken because Chromium disables compositing for RTL pages
-BUGWK56591 : compositing/rtl/rtl-absolute-overflow-scrolled.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-absolute-overflow.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-absolute.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-fixed-overflow-scrolled.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-fixed-overflow.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-fixed.html = TEXT
-BUGWK56591 : compositing/rtl/rtl-relative.html = TEXT
-
 BUGWK63033 : svg/custom/absolute-root-position-masking.xhtml = IMAGE
 BUGWK63036 MAC : svg/dom/SVGTransformList-basics.xhtml = IMAGE
 

Source/WebKit/chromium/ChangeLog

+2012-01-03  Adrienne Walker  <enne@google.com>
+
+        [chromium] Support RTL pages and elements in the compositor
+        https://bugs.webkit.org/show_bug.cgi?id=56591
+
+        Reviewed by James Robinson.
+
+        As the noncomposited content host layer is created and managed by the
+        Chromium compositor, adjust its transform appropriately in the layer
+        tree and at paint time to handle the offset required due to the
+        initial containing block of RTL pages.
+
+        * src/ChromeClientImpl.cpp:
+        (WebKit::ChromeClientImpl::allowedCompositingTriggers):
+        * src/NonCompositedContentHost.cpp:
+        (WebKit::NonCompositedContentHost::setViewport):
+        (WebKit::NonCompositedContentHost::paintContents):
+        * src/NonCompositedContentHost.h:
+        * src/WebViewImpl.cpp:
+        (WebKit::WebViewImpl::updateLayerTreeViewport):
+
 2012-01-03  Adrienne Walker  <enne@google.com>
 
         [chromium] Make tiled layer's tiler always exist

Source/WebKit/chromium/src/ChromeClientImpl.cpp

@@ -895,10 +895,6 @@ void ChromeClientImpl::scheduleCompositingLayerSync()
 
 ChromeClient::CompositingTriggerFlags ChromeClientImpl::allowedCompositingTriggers() const
 {
-    // FIXME: RTL style not supported by the compositor yet.
-    if (!m_webView->allowsAcceleratedCompositing() || m_webView->pageHasRTLStyle())
-        return 0;
-
     CompositingTriggerFlags flags = 0;
     Settings* settings = m_webView->page()->settings();
     if (settings->acceleratedCompositingFor3DTransformsEnabled())

Source/WebKit/chromium/src/NonCompositedContentHost.cpp

@@ -76,7 +76,7 @@ void NonCompositedContentHost::setScrollLayer(WebCore::GraphicsLayer* layer)
     ASSERT(scrollLayer());
 }
 
-void NonCompositedContentHost::setViewport(const WebCore::IntSize& viewportSize, const WebCore::IntSize& contentsSize, const WebCore::IntPoint& scrollPosition, float pageScale)
+void NonCompositedContentHost::setViewport(const WebCore::IntSize& viewportSize, const WebCore::IntSize& contentsSize, const WebCore::IntPoint& scrollPosition, float pageScale, int layerAdjustX)
 {
     if (!scrollLayer())
         return;
@@ -90,7 +90,16 @@ void NonCompositedContentHost::setViewport(const WebCore::IntSize& viewportSize,
     scrollLayer()->setScrollable(true);
     m_graphicsLayer->setSize(contentsSize);
 
-    if (visibleRectChanged)
+    m_layerAdjustX = layerAdjustX;
+    if (m_graphicsLayer->transform().m41() != m_layerAdjustX) {
+        WebCore::TransformationMatrix transform = m_graphicsLayer->transform();
+        transform.setM41(m_layerAdjustX);
+        m_graphicsLayer->setTransform(transform);
+
+        // If a tiled layer is shifted left or right, the content that goes into
+        // each tile will change. Invalidate the entire layer when this happens.
+        m_graphicsLayer->setNeedsDisplay();
+    } else if (visibleRectChanged)
         m_graphicsLayer->setNeedsDisplay();
 
     if (m_graphicsLayer->pageScaleFactor() != pageScale)
@@ -128,7 +137,10 @@ void NonCompositedContentHost::notifySyncRequired(const WebCore::GraphicsLayer*)
 
 void NonCompositedContentHost::paintContents(const WebCore::GraphicsLayer*, WebCore::GraphicsContext& context, WebCore::GraphicsLayerPaintingPhase, const WebCore::IntRect& clipRect)
 {
-    m_contentPaint->paint(context, clipRect);
+    context.translate(-m_layerAdjustX, 0);
+    WebCore::IntRect adjustedClipRect = clipRect;
+    adjustedClipRect.move(m_layerAdjustX, 0);
+    m_contentPaint->paint(context, adjustedClipRect);
 }
 
 bool NonCompositedContentHost::showDebugBorders() const

Source/WebKit/chromium/src/NonCompositedContentHost.h

@@ -57,7 +57,7 @@ public:
     void invalidateRect(const WebCore::IntRect&);
     void setBackgroundColor(const WebCore::Color&);
     void setScrollLayer(WebCore::GraphicsLayer*);
-    void setViewport(const WebCore::IntSize& viewportSize, const WebCore::IntSize& contentsSize, const WebCore::IntPoint& scrollPosition, float pageScale);
+    void setViewport(const WebCore::IntSize& viewportSize, const WebCore::IntSize& contentsSize, const WebCore::IntPoint& scrollPosition, float pageScale, int layerAdjustX);
     void protectVisibleTileTextures();
     WebCore::GraphicsLayer* topLevelRootLayer() const { return m_graphicsLayer.get(); }
 
@@ -77,6 +77,7 @@ private:
     OwnPtr<WebCore::GraphicsLayer> m_graphicsLayer;
     OwnPtr<WebCore::LayerPainterChromium> m_contentPaint;
     WebCore::IntSize m_viewportSize;
+    int m_layerAdjustX;
 };
 
 } // namespace WebKit

Source/WebKit/chromium/src/WebViewImpl.cpp

@@ -3063,7 +3063,15 @@ void WebViewImpl::updateLayerTreeViewport()
     IntRect visibleRect = view->visibleContentRect(true /* include scrollbars */);
     IntPoint scroll(view->scrollX(), view->scrollY());
 
-    m_nonCompositedContentHost->setViewport(visibleRect.size(), view->contentsSize(), scroll, pageScaleFactor());
+    int layerAdjustX = 0;
+    if (pageHasRTLStyle()) {
+        // The origin of the initial containing block for RTL root layers is not
+        // at the far left side of the layer bounds. Instead, it's one viewport
+        // width (not including scrollbars) to the left of the right side of the
+        // layer.
+        layerAdjustX = -view->contentsSize().width() + view->visibleContentRect(false).width();
+    }
+    m_nonCompositedContentHost->setViewport(visibleRect.size(), view->contentsSize(), scroll, pageScaleFactor(), layerAdjustX);
     m_layerTreeHost->setViewport(visibleRect.size());
     m_layerTreeHost->setPageScale(pageScaleFactor());
 }