Revert 202787 "Remove unnecessary ui::CompositorTestSupport"

Revert 202787 "Remove unnecessary ui::CompositorTestSupport"

Suspected to break Linux ChromeOS build
http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Full/builds/19953/steps/compile/logs/stdio

obj/ui/snapshot/test/snapshot_unittests.run_all_unittests.o:run_all_unittests.cc:function
main:error: undefined reference to
'ui::test::CompositorTestSuite::CompositorTestSuite(int, char**)'
obj/ui/snapshot/test/snapshot_unittests.run_all_unittests.o:run_all_unittests.cc:function
main:error: undefined reference to
'ui::test::CompositorTestSuite::~CompositorTestSuite()'


> Remove unnecessary ui::CompositorTestSupport
> 
> The ui::CompositorTestSupport class existed to initialize WebKit since
> ui::Compositor depends on cc which used to depend on WebKit being initialized
> to function properly.  cc no longer has this requirement, so this class is
> unnecessary.
> 
> R=piman, sky
> 
> Review URL: https://chromiumcodereview.appspot.com/14744016

TBR=jamesr@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=202790

[kinuko, 2013-05-29 07:17:05]

Committed patchset #1 manually as r202790.