Fix JBig2 decoding logic

Fix JBig2 decoding logic

While decoding among instances, variable "FIRSTS" should hold its
value, not be reset. This was accidently changed by earlier
refactoring.

BUG=chromium:625848, pdfium:636
Review-Url: https://codereview.chromium.org/2569023002
Committed: https://pdfium.googlesource.com/pdfium/+/8d5d00b7270c198f9bfafcbd764ba0eff70fd5b1

[Wei Li, 2016-12-12 21:23:13]

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

[commit-bot: I haz the power, 2016-12-12 21:23:22]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-12 21:38:32]

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

[commit-bot: I haz the power, 2016-12-12 21:38:33]

Dry run: This issue passed the CQ dry run.

[Wei Li, 2016-12-12 21:52:07]

weili@chromium.org changed reviewers:
+ dsinclair@chromium.org, tsepez@chromium.org

[Wei Li, 2016-12-12 21:52:08]

pls review, thanks

[dsinclair, 2016-12-12 21:58:21]

The CQ bit was checked by dsinclair@chromium.org

[dsinclair, 2016-12-12 21:58:21]

lgtm

[commit-bot: I haz the power, 2016-12-12 21:58:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-12 21:58:38]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1481579901270820, "parent_rev":
"d340646765ffebc4e41ed3021d05b1a792888a77", "commit_rev":
"8d5d00b7270c198f9bfafcbd764ba0eff70fd5b1"}

[commit-bot: I haz the power, 2016-12-12 21:58:40]

Description was changed from

==========
Fix JBig2 decoding logic

While decoding among instances, variable "FIRSTS" should hold its
value, not be reset. This was accidently changed by earlier
refactoring.

BUG=chromium:625848,pdfium:636
==========

to

==========
Fix JBig2 decoding logic

While decoding among instances, variable "FIRSTS" should hold its
value, not be reset. This was accidently changed by earlier
refactoring.

BUG=chromium:625848,pdfium:636

Review-Url: https://codereview.chromium.org/2569023002
Committed:
https://pdfium.googlesource.com/pdfium/+/8d5d00b7270c198f9bfafcbd764ba0eff70f...
==========

[commit-bot: I haz the power, 2016-12-12 21:58:41]

Committed patchset #1 (id:1) as
https://pdfium.googlesource.com/pdfium/+/8d5d00b7270c198f9bfafcbd764ba0eff70f...

[Tom Sepez, 2016-12-12 21:58:45]

lgtm