Cleanup RemotePlatformLayer when disconnecting RemoteFrame.

Source/core/rendering/RenderPart.cpp

Index: Source/core/rendering/RenderPart.cpp
diff --git a/Source/core/rendering/RenderPart.cpp b/Source/core/rendering/RenderPart.cpp
index 33f88c93b1e1551309a59f26fe37c25b975defc4..eb8ad23df8264a220c721e7c734ebd0aa6d49969 100644
--- a/Source/core/rendering/RenderPart.cpp
+++ b/Source/core/rendering/RenderPart.cpp
@@ -132,7 +132,7 @@ bool RenderPart::requiresAcceleratedCompositing() const
         return false;
 
     HTMLFrameOwnerElement* element = toHTMLFrameOwnerElement(node());
-    if (element->contentFrame() && element->contentFrame()->remotePlatformLayer())
+    if (element->contentFrame() && element->contentFrame()->isRemoteFrame())
         return true;
 
     if (Document* contentDocument = element->contentDocument()) {
@@ -166,10 +166,6 @@ bool RenderPart::nodeAtPoint(const HitTestRequest& request, HitTestResult& resul
     if (!widget() || !widget()->isFrameView() || !request.allowsChildFrameContent())
         return nodeAtPointOverWidget(request, result, locationInContainer, accumulatedOffset, action);
 
-    // FIXME: Until RemoteFrames use RemoteFrameViews, we need an explicit check here.
-    if (toFrameView(widget())->frame().isRemoteFrameTemporary())

[kenrb, 2015/01/23 18:31:02]

I am surprised if this does not break input events when running with
--site-per-process. The comment is stale because RemoteFrames now have
RemoteFrameViews, but don't we need to handle the case where widget() is a
RemoteFrameView below? Line 173 should crash as an invalid downcast.

[lfg, 2015/02/03 03:43:46]

RemoteFrameViews return false to isFrameView(), so they should be handled in the
if statement above this.

-        return nodeAtPointOverWidget(request, result, locationInContainer, accumulatedOffset, action);
-
     FrameView* childFrameView = toFrameView(widget());
     RenderView* childRoot = childFrameView->renderView();