https://bugs.webkit.org/show_bug.cgi?id=123422

Reviewed by Simon Fraser.

Add a PlatformCALayerRemote subclass that behaves similarly to
WebTiledBackingLayer, forwarding relevant things (setNeedsDisplay, etc.)
to the TileController which it owns.

Teach the remote layer tree code enough to proxy these layers across,
and paint them in a manner similar to WebSimpleLayer (just calling
straight back to the TileController to paint).

* Shared/mac/RemoteLayerTreeTransaction.h:
* Shared/mac/RemoteLayerTreeTransaction.mm:
(WebKit::RemoteLayerTreeTransaction::LayerProperties::encode):
(WebKit::RemoteLayerTreeTransaction::LayerProperties::decode):
(WebKit::dumpChangedLayers):
* UIProcess/mac/RemoteLayerTreeHost.mm:
(WebKit::RemoteLayerTreeHost::commit):
* WebProcess/WebPage/mac/PlatformCALayerRemote.cpp:
(PlatformCALayerRemote::setEdgeAntialiasingMask):
Add support for adjusting/encoding/decoding/dumping/applying edgeAntialiasingMask.

(WebKit::RemoteLayerTreeTransaction::dump):
Drive-by fix dumping of created layers to have one layer per line.

* UIProcess/mac/RemoteLayerTreeHost.mm:
(WebKit::RemoteLayerTreeHost::createLayer):
Create CALayers for Simple, TiledBacking, PageTiledBacking, and TiledBackingTile layers.

* WebKit2.xcodeproj/project.pbxproj:
Add PlatformCALayerRemoteTiledBacking.{h, cpp}.

* WebProcess/WebPage/mac/PlatformCALayerRemote.cpp:
(PlatformCALayerRemote::create):
Create a PlatformCALayerRemoteTiledBacking for TiledBacking and PageTiledBacking layers.

(PlatformCALayerRemote::removeAllSublayers):
Fix removeAllSublayers to make a copy of the PlatformCALayerList before
mutating it, to avoid crashes when iterating a mutated list.

* WebProcess/WebPage/mac/PlatformCALayerRemote.h:
Definalize PlatformCALayerRemote so we can have PlatformCALayerRemoteTiledBacking.
Note that we will use a tiled backing layer in some cases.
Make the constructor protected, not private, so our subclass can use it.

* WebProcess/WebPage/mac/PlatformCALayerRemoteTiledBacking.cpp: Added.
(PlatformCALayerRemoteTiledBacking::PlatformCALayerRemoteTiledBacking):
(PlatformCALayerRemoteTiledBacking::~PlatformCALayerRemoteTiledBacking):
(PlatformCALayerRemoteTiledBacking::setNeedsDisplay):
(PlatformCALayerRemoteTiledBacking::customSublayers):
(PlatformCALayerRemoteTiledBacking::setBounds):
(PlatformCALayerRemoteTiledBacking::isOpaque):
(PlatformCALayerRemoteTiledBacking::setOpaque):
(PlatformCALayerRemoteTiledBacking::acceleratesDrawing):
(PlatformCALayerRemoteTiledBacking::setAcceleratesDrawing):
(PlatformCALayerRemoteTiledBacking::setContentsScale):
(PlatformCALayerRemoteTiledBacking::setBorderWidth):
(PlatformCALayerRemoteTiledBacking::setBorderColor):
* WebProcess/WebPage/mac/PlatformCALayerRemoteTiledBacking.h: Added.
Add a subclass of PlatformCALayerRemote which forwards operations
to TileController, very similar to what WebTiledBackingLayer does.
It also owns the TileController, and overrides customSublayers() and
tiledBacking() to return the right thing.

* WebProcess/WebPage/mac/RemoteLayerBackingStore.mm:
(RemoteLayerBackingStore::display):
Teach RemoteLayerBackingStore about how to paint different kinds of layers.
Simple layers and Tile layers will call paintContents directly,
WebLayers will do what WebLayer does and use drawLayerContents.
Other kinds of layers won't paint at all right now.
I would like to centralize this behavior (and get rid of our CALayer
subclasses entirely, moving all that behavior to be shared between Mac,
Windows, and the remote layer tree), but that is a patch for another day.

* WebProcess/WebPage/mac/RemoteLayerTreeDrawingArea.h:
* WebProcess/WebPage/mac/RemoteLayerTreeDrawingArea.mm:
(WebKit::RemoteLayerTreeDrawingArea::RemoteLayerTreeDrawingArea):
(WebKit::RemoteLayerTreeDrawingArea::shouldUseTiledBackingForFrameView):
Force accelerated compositing on always when using the remote layer tree.
Use a TiledBacking for the main frame.

* WebProcess/WebPage/mac/TiledCoreAnimationDrawingArea.h:
Drive-by OVERRIDE.

* WebCore.exp.in:
* WebCore.xcodeproj/project.pbxproj:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@158223 268f45cc-cd09-0410-ab3c-d52691b4dbfc