LayerClient's base class (PlatformCALayerClient) method signature for abstract method platformCALayerShowRepaintCounter was updated in http://trac.webkit.org/changeset/130676 so it needs to be changed in LayerClient as well.
Created attachment 168446 [details]
Attachment 168446 [details] did not pass style-queue:
Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'Source/WebCore/ChangeLog', u'Source/WebCor..." exit_code: 1
Source/WebCore/ChangeLog:1: ChangeLog entry has no bug number [changelog/bugnumber] 
Total errors found: 1 in 2 files
If any of these errors are false positives, please file a bug against check-webkit-style.
Why didn't this break the build?
AVCF is disabled on OpenSource
Created attachment 168450 [details]
Comment on attachment 168450 [details]
We should really make platformCALayerClient non-pure to avoid all these overrides.