Compile webkit gpu code in an upstream build too.
Compile webkit gpu code in an upstream build too.

I had originally disabled this when setting up the upstream
webkit.org build.  At the time we didn't compile any of src/gpu,
but now we do, so it's safe to enable this.

If we don't compile this, shared library (.so) builds in a
webkit only tree fail to link because of missing symbols.

Review URL: http://codereview.chromium.org/3722002

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@62330 0039d316-1c4b-4281-b951-d872f2087c98

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