Add hooks for external run-time reference adoption checks to SkRefCnt.

The reference adoption checks are to help detect memory
leaks and bad usage when using SkRefCnt subclasses with
Blink's RefPtr.

BUG=crbug.com/304265
R=reed@google.com, bungeman@google.com

Author: junov@chromium.org

Review URL: https://codereview.chromium.org/25432003

git-svn-id: http://skia.googlecode.com/svn/trunk/include@11811 2bbb7eff-a529-9590-31e7-b0007b416f81
1 file changed