Allow multiple concurrent timers.

BUG=
R=robertphillips@google.com

Author: jcgregorio@google.com

Review URL: https://codereview.chromium.org/118473006

git-svn-id: http://skia.googlecode.com/svn/trunk@12802 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed