Revert of Revert[4] of add asserts around results from requestLock

Revert of Revert[4] of add asserts around results from requestLock (patchset #3 id:40001 of https://codereview.chromium.org/1159733006/)

Reason for revert:
gfx_unittests (under linux_asan)

TEST_F(RenderTextTest, NewlineWithoutMultilineFlag) fails

@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@Direct leak of 368 byte(s) in 1 object(s) allocated from:@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@    #0 0x4cc74b in __interceptor_malloc (/b/build/slave/linux_asan/build/src/out/Release/gfx_unittests+0x4cc74b)@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@    #1 0x7f2f7060ebdf in _cairo_image_surface_create_for_pixman_image /build/buildd/cairo-1.10.2/src/cairo-image-surface.c:158@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@Indirect leak of 256 byte(s) in 1 object(s) allocated from:@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@    #0 0x4cc74b in __interceptor_malloc (/b/build/slave/linux_asan/build/src/out/Release/gfx_unittests+0x4cc74b)@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@    #1 0x7f2f6c7be26a in _pixman_image_allocate /build/buildd/pixman-0.30.2/build/pixman/../../pixman/pixman-image.c:184@@@
@@@STEP_LOG_LINE@RenderTextTest.HarfBuzz_HorizontalPositions@@@@


I think they are creating a cairo surface, but it has no pixels (zero size?). In this CL, if I see no pixels, I ignore the call-back which is used to free the surface (doh).


Original issue's description:
> Revert[4] of add asserts around results from requestLock
> 
> This reverts commit 19663e54c017499406036746e7689193aa6417e6.
> 
> BUG=skia:
> TBR=
> 
> Committed: https://skia.googlesource.com/skia/+/df91b73a34e3a306c93a5e320704736255c3d9f0

TBR=reed@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Committed: https://skia.googlesource.com/skia/+/11e833d91b5ba2193ed593cb74900dddbec24b6f

[reed2, 2015-05-30 16:20:18]

Created Revert of Revert[4] of add asserts around results from requestLock

[commit-bot: I haz the power, 2015-05-30 16:20:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1151063005/1

[commit-bot: I haz the power, 2015-05-30 16:20:33]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/11e833d91b5ba2193ed593cb74900dddbec24b6f