GitLab

This moves a clear per picture into a clear-to-background color
per picture pile. We need this to ensure that a solid color
page in low res is considered solid, since all the draws are
of the same color.

BUG=233622

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=198272
"

TBR=reveman

Review URL: https://chromiumcodereview.appspot.com/14322017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198826 0039d316-1c4b-4281-b951-d872f2087c98