Turn on use_skia by default for Mac

BUG=101731
Review URL: http://codereview.chromium.org/8890034

git-svn-id: http://src.chromium.org/svn/trunk/src/build@113807 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

use_skia_on_mac.gypi

@@ -5,5 +5,5 @@
 # Whether the Mac port uses Skia (instead of Core Graphics) by default.
 # This overrides the setting in common.gypi .
 {
-  'use_skia_on_mac%': 0,
+  'use_skia_on_mac%': 1,
 }