Attempt to do a bona-fide end-to-end Chrome QUIC test.

BUG=

Review URL: https://codereview.chromium.org/23654054

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225901 0039d316-1c4b-4281-b951-d872f2087c98
[Activity Log] Replace extension ID in the browser tests with a constant

Replace repeated occurrences of the extension activity log test
extension (in the browser tests) with a string constant, to make it
easier to update the extension ID if we ever need to do that.

Review URL: https://codereview.chromium.org/23934013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225902 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225901
Correctly resets long press timer when entering chording mode.
BUG=297586

Review URL: https://codereview.chromium.org/25023004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225903 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225903