Plumb through --disable-accelerated-2d-canvas.
Plumb through --disable-accelerated-2d-canvas.

So we can disable it in guest mode on CrOS M19.

BUG=120078
TEST=none

Review URL: https://chromiumcodereview.appspot.com/9918010

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@129618 0039d316-1c4b-4281-b951-d872f2087c98

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