Symmetric rendering when >20px with DirectWrite.

If the font has a gasp table use it to determine symmetric. Otherwise,
use symmetric if the the font isn't hinted or is >20px. The remaining
cases use non-symmetric.

BUG=chromium:706792,skia:6432

Change-Id: I91b66a9615aae27c195e1545298a9d36bc58a705
Reviewed-on: https://skia-review.googlesource.com/11400
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
1 file changed