[pdf] Allow invalidation during paint.

[pdf] Allow invalidation during paint.

When JavaScript fires inside a PDF document it's possible to trigger an
invalidation while the paint manager is painting. This CL allows the
invalidation instead of triggering a DCHECK.

BUG=chromium:681351

[dsinclair, 2017-01-19 14:53:08]

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

[commit-bot: I haz the power, 2017-01-19 14:53:30]

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

[dsinclair, 2017-01-19 14:53:36]

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

[dsinclair, 2017-01-19 14:53:37]

PTAL.

Not sure who the right person to review this would be? I'm not very familiar
with this code, so this is a guess at the correct behaviour.

[dsinclair, 2017-01-19 14:54:01]

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

[commit-bot: I haz the power, 2017-01-19 14:54:06]

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, 2017-01-19 15:35:59]

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

[commit-bot: I haz the power, 2017-01-19 15:36:00]

Dry run: This issue passed the CQ dry run.

[Tom Sepez, 2017-01-19 17:43:37]

https://codereview.chromium.org/2641163002/diff/1/pdf/paint_manager.cc
File pdf/paint_manager.cc (right):

https://codereview.chromium.org/2641163002/diff/1/pdf/paint_manager.cc#newcod...
pdf/paint_manager.cc:144: // Note, we can't DCHECK(!in_paint_) here because
javascript inside the
Do we just want to no-op it in this special case?  Continuing might re-enter
things that weren't expecting it ...

[dsinclair, 2017-01-19 18:56:10]

https://codereview.chromium.org/2641163002/diff/1/pdf/paint_manager.cc
File pdf/paint_manager.cc (right):

https://codereview.chromium.org/2641163002/diff/1/pdf/paint_manager.cc#newcod...
pdf/paint_manager.cc:144: // Note, we can't DCHECK(!in_paint_) here because
javascript inside the
On 2017/01/19 17:43:37, Tom Sepez wrote:
> Do we just want to no-op it in this special case?  Continuing might re-enter
> things that weren't expecting it ...


I don't know. My concern when I did this originally was that we'd lose the
invalidation as it won't get added to the aggregator_.InvalidateRect() below. Is
that going to leave us failing to paint something we should have painted?

As I said, I don't understand this code well enough to know which is the right
direction to go .....