Remove codes related to scaling in GraphicsLayer tree.

There are three kind of codes:
1. getters of page/device scale.
2. callbacks when page/device scale is changed.
3. layer pixel aligned booleans.

All codes are not used, so this patch removes all.

BUG=

Review URL: https://chromiumcodereview.appspot.com/14974003

git-svn-id: svn://svn.chromium.org/blink/trunk@150298 bbb929c8-8fbe-4397-9dbb-9b2b20218538
10 files changed