cc: Add layer eviction tile iterator.
This patch adds an eviction tile iterator to the layer. The iterator
returns tiles as provided by the tiling eviction tile iterator. It
returns all tiles in the following order:
1. Prepaint tiles from higher than high-res non-ideal tilings.
2. Prepaint tiles from lower than high-res non-ideal tilings.
3. Prepaint tiles from low res tiling.
4. Prepaint tiles from high res tiling.
5. Visible tiles from higher than high-res non-ideal tilings.
6. Visible tiles from lower than high-res non-ideal tilings.
7. Visible tiles from low res tiling.
8. Visible tiles from high res tiling.
R=enne
Review URL: https://codereview.chromium.org/
221413005
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262310 0039d316-1c4b-4281-b951-d872f2087c98