SkPDF: SkBitSet gets reset() to make drop() better.

SkPDF: SkBitSet gets reset() to make drop() better.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2354583002

Committed: https://skia.googlesource.com/skia/+/e202bd8b71f6aa184c2c8ce6f653755de1331c88

[hal.canary, 2016-09-19 15:24:22]

Description was changed from

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SkPDF: SkBitSet gets reset() to make drop() better.

BUG=skia:
==========

to

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SkPDF: SkBitSet gets reset() to make drop() better.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2354583002
==========

[hal.canary, 2016-09-19 15:25:07]

The CQ bit was checked by halcanary@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-09-19 15:25:17]

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, 2016-09-19 15:59:27]

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

[commit-bot: I haz the power, 2016-09-19 15:59:28]

Dry run: This issue passed the CQ dry run.

[hal.canary, 2016-09-19 16:04:54]

halcanary@google.com changed reviewers:
+ bungeman@google.com

[hal.canary, 2016-09-19 16:04:55]

I missed this in the last refactor.

[bungeman-skia, 2016-09-19 17:07:08]

https://codereview.chromium.org/2354583002/diff/1/src/pdf/SkPDFFont.cpp
File src/pdf/SkPDFFont.cpp (right):

https://codereview.chromium.org/2354583002/diff/1/src/pdf/SkPDFFont.cpp#newco...
src/pdf/SkPDFFont.cpp:728: void SkPDFFont::drop() {
Now I'm wierded out about this 'drop' method which I wan't previously familiar
with. This looks essentially like a destructor (it's even necessary to call
<super>::drop()), and after calling it the object is a bit of a zombie, is it
not (it's kinda in a moved-from state)?

The only real caller appears to be the SkPDFObjectSerializer which is very
obliquely moving all the data out of the PDFObjects it serializes (essentially
making them no longer valid, but also stating that they won't be used again). It
seems to 'drop' them instead of just deleting them because some other structure
(the canon?) may be holding on to these now zombie objects (without a good
reason I can tell) just so they can then be deleted later.

I'd rather see that logic cleaned up than have it leak out and start infecting
the SkBitSet class. It seems like the use of 'drop' (on a reference counted
object) is just asking for difficult to find bugs.

https://codereview.chromium.org/2354583002/diff/1/src/pdf/SkPDFFont.cpp#newco...
src/pdf/SkPDFFont.cpp:730: fGlyphUsage.reset();
If this guy is really gone maybe just destruct?

https://codereview.chromium.org/2354583002/diff/1/src/utils/SkBitSet.h
File src/utils/SkBitSet.h (right):

https://codereview.chromium.org/2354583002/diff/1/src/utils/SkBitSet.h#newcode27
src/utils/SkBitSet.h:27: fDwordCount = 0;
This seems a bit strange. Previous to this fDwordCount and fBitData could have
been marked 'const', now they cannot.

[hal.canary, 2016-09-19 17:10:01]

The CQ bit was checked by halcanary@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-09-19 17:10:09]

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

[bungeman-skia, 2016-09-19 17:13:24]

lgtm to fix this for now. Long term, this 'drop' thing is icky.

[hal.canary, 2016-09-19 17:13:50]

The CQ bit was unchecked by halcanary@google.com

[hal.canary, 2016-09-19 17:13:54]

The CQ bit was checked by halcanary@google.com

[commit-bot: I haz the power, 2016-09-19 17:14:00]

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, 2016-09-19 17:27:06]

Description was changed from

==========
SkPDF: SkBitSet gets reset() to make drop() better.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2354583002
==========

to

==========
SkPDF: SkBitSet gets reset() to make drop() better.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2354583002

Committed:
https://skia.googlesource.com/skia/+/e202bd8b71f6aa184c2c8ce6f653755de1331c88
==========

[commit-bot: I haz the power, 2016-09-19 17:27:07]

Committed patchset #2 (id:20001) as
https://skia.googlesource.com/skia/+/e202bd8b71f6aa184c2c8ce6f653755de1331c88