Limit pixels that get cleared to repaint area.
commit864b846301f7e59f964a988a14c0eb11ee856adb
authorvangelis@chromium.org <vangelis@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>
Thu, 7 Nov 2013 08:02:03 +0000 (7 08:02 +0000)
committervangelis@chromium.org <vangelis@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98>
Thu, 7 Nov 2013 08:02:03 +0000 (7 08:02 +0000)
treee2a09b17b484b3f7bafc5e997a24409bf453110f
parent5248357eff4759ec3f905b9fa271ba9496259f92
Limit pixels that get cleared to repaint area.

Since we now keep the canvas around in the ContentLayerUpdater, we often
end up getting small invalidations that paint on a large canvas. In those
cases, instead of clearing the entire canvas to transparent, clear only the
portion that will be repainted.

BUG=313494

Review URL: https://codereview.chromium.org/61403003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233539 0039d316-1c4b-4281-b951-d872f2087c98
cc/resources/content_layer_updater.cc