Add extra warnings to match what Android uses.

R=mtklein@google.com

Committed: https://code.google.com/p/skia/source/detail?r=12310

Review URL: https://codereview.chromium.org/74193005

git-svn-id: http://skia.googlecode.com/svn/trunk/src@12314 2bbb7eff-a529-9590-31e7-b0007b416f81
3 files changed