Do not clip inside OcclusionTracker.

Assume that content-rect is already clipped. This allows us to
early-out from occlusion testing when there is no occlusion.

BUG=276725

Review URL: https://codereview.chromium.org/23708021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227133 0039d316-1c4b-4281-b951-d872f2087c98
Remove chromium.perf dependency on PyAuto.

The chromium.perf waterfall previously depended on PyAuto for the network
simulation benchmarks. They have now been migrated to Telemetry.

Hence, we can avoid building PyAuto now.

BUG=

Review URL: https://codereview.chromium.org/25399004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227134 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227133
Hide "add to homescreen" on bookmarks page properly

The conditions changed so that the feature is enabled by default
on Beta and below.

BUG=303831

Review URL: https://codereview.chromium.org/25589004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227135 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227135