Increase safety of PictureTest

When gather pixel refs was broken, REPORTER_ASSERT(data) realized that data was NULL, but subsequent lines dereferenced it anyway, and so segfaulted.

Committed: http://code.google.com/p/skia/source/detail?r=9933

[tomhudson, 2013-07-09 14:23:09]

I think anybody on the team could review this, but Mike, you wrote the original
code.

[reed1, 2013-07-09 14:28:14]

https://codereview.chromium.org/18904003/diff/3/tests/PictureTest.cpp
File tests/PictureTest.cpp (right):

https://codereview.chromium.org/18904003/diff/3/tests/PictureTest.cpp#newcode191
tests/PictureTest.cpp:191: REPORTER_ASSERT(reporter, NULL != data);
If we're going to do nothing if data is NULL, it think the subsequent asserts
would be easier to read if we just say continue here.

e.g.

if (!data) {
    continue;
}

or

if (data) {
    int count = ...
    REPORTER_ASSERT ...
}

[tomhudson, 2013-07-09 14:57:37]

Oops, the "NULL !=" isn't necessary, that was part of my initial guess about the
problem.

https://codereview.chromium.org/18904003/diff/3/tests/PictureTest.cpp
File tests/PictureTest.cpp (right):

https://codereview.chromium.org/18904003/diff/3/tests/PictureTest.cpp#newcode191
tests/PictureTest.cpp:191: REPORTER_ASSERT(reporter, NULL != data);
On 2013/07/09 14:28:14, reed1 wrote:
> If we're going to do nothing if data is NULL, it think the subsequent asserts
> would be easier to read if we just say continue here.
> 
> e.g.
> 
> if (!data) {
>     continue;
> }
> 
> or
> 
> if (data) {
>     int count = ...
>     REPORTER_ASSERT ...
> }

Done.

[reed1, 2013-07-09 15:19:54]

lgtm

[commit-bot: I haz the power, 2013-07-09 15:31:50]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/tomhudson@chromium.org/18904003/6001

[commit-bot: I haz the power, 2013-07-09 16:04:34]

Change committed as 9933