Merge the background paint phase into the foreground phase.

Merge the background paint phase into the foreground phase.

First step in getting rid of paint phases. Verified that
deleting this phase entirely would cause flights-app-pixel.sky
to fail and that it still passes in this patch, which just does
the background painting as part of the foreground phase.

R=esprehn@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/efc3afd428bd85fd3d12e0dc941b5eb7248ca30b

[ojan, 2015-01-26 05:19:25]

ojan@chromium.org changed reviewers:
+ abarth@chromium.org, eseidel@chromium.org, esprehn@chromium.org

[esprehn, 2015-01-26 17:22:23]

lgtm

[ojan, 2015-01-26 23:52:54]

Committed patchset #1 (id:1) manually as
efc3afd428bd85fd3d12e0dc941b5eb7248ca30b (presubmit successful).