Use is<>() / downcast<>() for PlatformCALayer subclasses
https://bugs.webkit.org/show_bug.cgi?id=137661

Reviewed by Simon Fraser.

Source/WebCore:

Use is<>() / downcast<>() for PlatformCALayer subclasses and clean up
the surrounding code.

No new tests, no behavior change.

* platform/graphics/ca/GraphicsLayerCA.cpp:
(WebCore::GraphicsLayerCA::ensureStructuralLayer):
(WebCore::GraphicsLayerCA::updateContentsRects):
(WebCore::GraphicsLayerCA::updateReplicatedLayers):
(WebCore::GraphicsLayerCA::swapFromOrToTiledLayer):
(WebCore::GraphicsLayerCA::fetchCloneLayers): Deleted.
* platform/graphics/ca/PlatformCALayer.h:
* platform/graphics/ca/TileCoverageMap.cpp:
(WebCore::TileCoverageMap::TileCoverageMap):
* platform/graphics/ca/TileGrid.cpp:
(WebCore::TileGrid::ensureTilesForRect):
* platform/graphics/ca/mac/PlatformCALayerMac.h:
* platform/graphics/ca/mac/PlatformCALayerMac.mm:
(PlatformCALayerMac::clone):
(PlatformCALayerMac::appendSublayer):
(PlatformCALayerMac::insertSublayer):
(PlatformCALayerMac::replaceSublayer):
(PlatformCALayerMac::adoptSublayers):
(PlatformCALayerMac::copyFiltersFrom):
* platform/graphics/ca/win/CACFLayerTreeHost.cpp:
(WebCore::CACFLayerTreeHost::setRootChildLayer):
* platform/graphics/ca/win/PlatformCALayerWin.cpp:
(PlatformCALayerWin::clone):
(PlatformCALayerWin::rootLayer):
(PlatformCALayerWin::appendSublayer):
(PlatformCALayerWin::insertSublayer):
(PlatformCALayerWin::replaceSublayer):
(PlatformCALayerWin::adoptSublayers):
(PlatformCALayerWin::copyFiltersFrom):
* platform/graphics/ca/win/PlatformCALayerWin.h:
* platform/graphics/ca/win/PlatformCALayerWinInternal.cpp:
(PlatformCALayerWinInternal::insertSublayer):
* platform/graphics/ca/win/PlatformCALayerWinInternal.h:

Source/WebKit/win:

Use is<>() / downcast<>() for PlatformCALayer subclasses and clean up
the surrounding code.

* FullscreenVideoController.cpp:
(FullscreenVideoController::enterFullscreen):

Source/WebKit2:

Use is<>() / downcast<>() for PlatformCALayer subclasses and clean up
the surrounding code.

* WebProcess/WebPage/mac/PlatformCALayerRemote.cpp:
(WebKit::PlatformCALayerRemote::~PlatformCALayerRemote):
(WebKit::PlatformCALayerRemote::updateClonedLayerProperties):
(WebKit::PlatformCALayerRemote::recursiveBuildTransaction):
(WebKit::PlatformCALayerRemote::setSublayers):
(WebKit::PlatformCALayerRemote::appendSublayer):
(WebKit::PlatformCALayerRemote::insertSublayer):
(WebKit::PlatformCALayerRemote::replaceSublayer):
(WebKit::PlatformCALayerRemote::adoptSublayers):
(WebKit::PlatformCALayerRemote::setMask):
(WebKit::PlatformCALayerRemote::copyFiltersFrom):
* WebProcess/WebPage/mac/PlatformCALayerRemote.h:
* WebProcess/WebPage/mac/PlatformCALayerRemoteCustom.h:
* WebProcess/WebPage/mac/RemoteLayerTreeContext.mm:
(WebKit::RemoteLayerTreeContext::buildTransaction):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@174657 268f45cc-cd09-0410-ab3c-d52691b4dbfc