Add quirk to disable overflow: hidden on main frame for Android WebView.

This feature wasn't supported on classic WebView and many apps
turn out to put one on their body element without intending to
disable scrolling.  This quirk will only apply to apps targeting an
older SDK version than the current one.

NOTRY=true
BUG=295287

Review URL: https://chromiumcodereview.appspot.com/23484064

git-svn-id: svn://svn.chromium.org/blink/trunk@158142 bbb929c8-8fbe-4397-9dbb-9b2b20218538