Merge paintControlTints into updateControlTints and remove the Internals call.

Exposing this for these tests is crazy since there's currently only one
caller left of updateControlTints. So whatever code these tests were
hitting can't be hit this way anymore.

BUG=343758

Review URL: https://codereview.chromium.org/166043007

git-svn-id: svn://svn.chromium.org/blink/trunk@167239 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove setPreserves3d from the WebLayer API

cc no longer uses it. It's time for it to go.

R=jamesr@chromium.org
BUG=None

Review URL: https://codereview.chromium.org/165963002

git-svn-id: svn://svn.chromium.org/blink/trunk@167240 bbb929c8-8fbe-4397-9dbb-9b2b20218538