Moved misplaced allDataReceived() assert

Moved misplaced allDataReceived() assert

The spots where allDataReceived() was checked in an if statement, or
asserted against were switched, so the release build was going right
through the code in getYUVComponentSizes(), without returning early,
which could lead to a crash.

Added safety checks inside the JPEG decoder just in case we get into
this situation some other way.

BUG=410788, 410586
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181439

[sugoi1, 2014-09-04 20:53:10]

sugoi@chromium.org changed reviewers:
+ noel@chromium.org

[sugoi1, 2014-09-04 20:53:59]

sugoi@chromium.org changed reviewers:
+ junov@chromium.org

[Noel Gordon, 2014-09-05 02:43:42]

lgtm

[Noel Gordon, 2014-09-05 02:47:07]

The CQ bit was checked by noel@chromium.org

[commit-bot: I haz the power, 2014-09-05 02:47:36]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sugoi@chromium.org/528293003/1

[commit-bot: I haz the power, 2014-09-05 02:55:48]

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

[commit-bot: I haz the power, 2014-09-05 02:55:49]

Try jobs failed on following builders:
  blink_presubmit on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/blink_presubmit/builds/1...)

[Noel Gordon, 2014-09-05 03:04:30]

+tkent for a rubber stamp.

[Noel Gordon, 2014-09-05 03:06:17]

noel@chromium.org changed reviewers:
+ tkent@chromium.org

[tkent, 2014-09-05 05:41:13]

rs lgtm

[tkent, 2014-09-05 05:41:17]

The CQ bit was checked by tkent@chromium.org

[commit-bot: I haz the power, 2014-09-05 05:42:11]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sugoi@chromium.org/528293003/1

[commit-bot: I haz the power, 2014-09-05 05:47:44]

Committed patchset #1 (id:1) as 181439