Proxy private UMA pepper interface for out-of-process and NaCl plugins.

BUG=317833

Review URL: https://codereview.chromium.org/61643022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246962 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246962
Add F5 (reload), back and forward key accelerators to the Aura-based content shell.

BUG=none

Review URL: https://codereview.chromium.org/143983015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@246963 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 246963