https://bugs.webkit.org/show_bug.cgi?id=104396

Reviewed by Adrienne Walker.

Source/WebCore:

This enables and implements the GraphicsLayer::setContentsToSolidColor
path for Chromium.

Tested by reftests in compositing/background-color/ and several other
compositing/ tests.

* platform/graphics/GraphicsLayer.h:
(WebCore::GraphicsLayer::supportsBackgroundColorContent):
* platform/graphics/chromium/GraphicsLayerChromium.cpp:
(WebCore::GraphicsLayerChromium::setContentsToSolidColor):
(WebCore):
* platform/graphics/chromium/GraphicsLayerChromium.h:
(WebKit):
(GraphicsLayerChromium):

Source/WebKit/chromium:

Updates some unit tests for better include discipline.

* tests/GraphicsLayerChromiumTest.cpp:
* tests/ImageLayerChromiumTest.cpp:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@146826 268f45cc-cd09-0410-ab3c-d52691b4dbfc