GitLab

Improve performance by reducing the number of bitmap copying.
BUG=chromium-os:12543
TEST=make sure network connecting looks the same
Review URL: http://codereview.chromium.org/6591017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@76318 0039d316-1c4b-4281-b951-d872f2087c98