Merge CompositedScrollingForFrames into PreferCompositingToLCDText

Remove the CompositedScrollingForFrames setting and change any callers
to use PreferCompositingToLCDText instead.

R=abarth
BUG=365851

Review URL: https://codereview.chromium.org/480803002

git-svn-id: svn://svn.chromium.org/blink/trunk@180466 bbb929c8-8fbe-4397-9dbb-9b2b20218538