Verify that the image is not empty before calling memset().

Verify that the image is not empty before calling memset().

Building with _FORTIFY_SOURCE=2 and NDEBUG set makes glibc complain that the
call to memset() in TestGraphics2D::TestInitToZero() can have a 0-byte size
argument.

Avoid the warning by asserting that the image does have a valid area before
using its height in the call to memset().

R=brettw, yzshen
BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=194893

[brettw, 2013-04-17 17:44:27]

I will defer to Yuzhu.

[brettw, 2013-04-17 17:45:13]

Actually, Yuzhu may be out. LGTM.

[Raphael Kubo da Costa (rakuco), 2013-04-17 17:51:56]

On 2013/04/17 17:45:13, brettw wrote:
> Actually, Yuzhu may be out. LGTM.

Thanks. Can you land this to me since I'm not a committer? FWIW, the entry to
AUTHORS is being added in 14296005.

[brettw, 2013-04-17 17:54:26]

The CQ is offline now (crbug.com/231428) and I don't have time to do a manual
landing. If you notice that bug is fixed and I haven't pressed the CQ button,
can you ping me to do that?

[commit-bot: I haz the power, 2013-04-18 07:26:08]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/raphael.kubo.da.costa@intel.com/140870...

[commit-bot: I haz the power, 2013-04-18 07:26:09]

Presubmit check for 14087009-1 failed and returned exit status 1.

INFO:root:Found 1 file(s).
INFO:PRESUBMIT:Valid authors are *@chromium.org, *@google.com,
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Running presubmit commit checks ...
Running /b/commit-queue/workdir/chromium/PRESUBMIT.py
Running /b/commit-queue/workdir/chromium/ppapi/PRESUBMIT.py

** Presubmit Messages **
If this change has an associated bug, add BUG=[bug number].

** Presubmit Warnings **
raphael.kubo.da.costa@intel.com is not in AUTHORS file. If you are a new
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If you are a chromite, verify the contributor signed the CLA.

[commit-bot: I haz the power, 2013-04-18 10:24:54]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/raphael.kubo.da.costa@intel.com/140870...

[commit-bot: I haz the power, 2013-04-18 12:07:25]

Change committed as 194893