Zero jpeg_decompress_struct before calling jpeg_calc_output_dimensions().

Zero jpeg_decompress_struct before calling jpeg_calc_output_dimensions().

https://uberchromegw.corp.google.com/i/client.skia/builders/Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-Valgrind/builds/38/steps/dm/logs/stdio

(Must have been https://codereview.chromium.org/1076923002 ?) 

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/f7aaadb570d56d34b0e364e65f9374a01665a528

[mtklein_C, 2015-04-16 12:12:35]

The CQ bit was checked by mtklein@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-04-16 12:12:54]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1094603002/1

[mtklein_C, 2015-04-16 12:14:48]

mtklein@chromium.org changed reviewers:
+ scroggo@google.com

[commit-bot: I haz the power, 2015-04-16 12:19:47]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-04-16 12:19:48]

This issue passed the CQ dry run.

[scroggo, 2015-04-16 13:09:07]

The CQ bit was checked by scroggo@google.com

[scroggo, 2015-04-16 13:09:08]

lgtm

[commit-bot: I haz the power, 2015-04-16 13:09:21]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1094603002/1

[commit-bot: I haz the power, 2015-04-16 13:09:31]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/f7aaadb570d56d34b0e364e65f9374a01665a528

[msarett, 2015-04-20 13:15:04]

msarett@google.com changed reviewers:
+ msarett@google.com

[msarett, 2015-04-20 13:15:04]

Nice catch!  Thanks!