37742976 - Catch bad gifs

* A security researcher crafted a gif that would cause the Android
Bitmap code to throw an NPE. That would cause messaging to crash when
decoding the NPE. Catch the NPE.

Test: manually tested the "crash.gif" attached to the bug. Stepped
through the debugger to verify we're catching the NPE and logging
the attempt. Verified normal gifs still work.

BUG=37742976

Change-Id: Iab814d5b0b514bed0cecddd9a76f1fc095f90892
1 file changed