Remove state from RebuildCrossRef state-machine.

Remove state from RebuildCrossRef state-machine.

The state '12' is only used once. This CL folds the contents of state 12 back
into the place where we set our state to 12.

This works because all state 12 does is decrement the loop counter so we process
the same character again and move us to state 0.

R=thestig@chromium.org

Committed: https://pdfium.googlesource.com/pdfium/+/395fbedc65e1261f1fb9189205501f4856235290

[dsinclair, 2015-11-04 17:37:19]

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

[dsinclair, 2015-11-04 17:37:19]

PTAL.

[Lei Zhang, 2015-11-04 18:13:47]

lgtm

[dsinclair, 2015-11-04 18:58:17]

Committed patchset #1 (id:1) manually as
395fbedc65e1261f1fb9189205501f4856235290 (presubmit successful).

[Tom Sepez, 2015-11-04 19:00:03]

LGTM.  

As an aside, I've been really reluctant to mess with this given the fragility of
the way it's coded. If you're looking for a follow-up, one of the things I'd
consider is moving all of the "actions" performed apart from parsing into their
own functions so that this loop is just about traversing characters and
manipulating state.

[dsinclair, 2015-11-04 19:02:31]

On 2015/11/04 19:00:03, Tom Sepez wrote:
> LGTM.  
> 
> As an aside, I've been really reluctant to mess with this given the fragility
of
> the way it's coded. If you're looking for a follow-up, one of the things I'd
> consider is moving all of the "actions" performed apart from parsing into
their
> own functions so that this loop is just about traversing characters and
> manipulating state.


That's the plan. My current goal is just to name the states as my little brain
can't handle seeing case: 1 {state = 3}; case 4: {state = 12;} and actualling
understanding what's happening.