Discard absurd values (and log warnings) when graphing bench results.

BUG=http://code.google.com/p/skia/issues/detail?id=596
Review URL: https://codereview.appspot.com/6197066

git-svn-id: http://skia.googlecode.com/svn/trunk@3914 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed