Add test that confirms Pictures don't leak pixel refs.

Have been investigating memory leak failures that show SkRecords'
ImmutableBitmap copy leaking.  I think this test proves its not
an obvious problem with ImmutableBitmap or SkRecord.

http://build.chromium.org/p/chromium.memory/builders/Linux%20Chromium%20OS%20ASan%20LSan%20Tests%20%282%29/builds/2509/steps/interactive_ui_tests/logs/stdio

BUG=skia:
R=bungeman@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/516593002
1 file changed