Simplify rowsDecoded returned by incrementalDecode

Simplify rowsDecoded returned by incrementalDecode

When sampling, we previously had to figure out the number of rows that
were written to the output based on the value reported by
incrementalDecode. (We also messed up the first time - see the fix in
crrev.com/2343153003.)

Instead, make incrementalDecode report the actual number of rows
written to. This can be provided directly to fill.

Make SkPngCodec report the correct number of rows, by incrementing its
count when it actually writes to the destination.

This also will simplify my in progress GIF change.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2407543002

Committed: https://skia.googlesource.com/skia/+/ff9f7bbef6fdbd2ae7965ff18981aa8df33abd96

[scroggo_chromium, 2016-10-07 21:04:34]

Description was changed from

==========
Simplify rowsDecoded returned by incrementalDecode

When sampling, we previously had to figure out the number of rows that
were written to the output based on the value reported by
incrementalDecode. (We also messed up the first time - see the fix in
crrev.com/2343153003.)

Instead, make incrementalDecode report the actual number of rows
written to. This can be provided directly to fill.

Make SkPngCodec report the correct number of rows, by incrementing its
count when it actually writes to the destination.

This also will simplify my in progress GIF change.
==========

to

==========
Simplify rowsDecoded returned by incrementalDecode

When sampling, we previously had to figure out the number of rows that
were written to the output based on the value reported by
incrementalDecode. (We also messed up the first time - see the fix in
crrev.com/2343153003.)

Instead, make incrementalDecode report the actual number of rows
written to. This can be provided directly to fill.

Make SkPngCodec report the correct number of rows, by incrementing its
count when it actually writes to the destination.

This also will simplify my in progress GIF change.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2407543002
==========

[scroggo_chromium, 2016-10-07 21:04:58]

scroggo@chromium.org changed reviewers:
+ msarett@google.com

[msarett, 2016-10-10 17:19:58]

lgtm

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkPngCodec.cpp
File src/codec/SkPngCodec.cpp (right):

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkPngCodec.cpp#ne...
src/codec/SkPngCodec.cpp:545: // FIXME: Can we remove fLinesDecoded and just
rely on fRowsWrittenToOutput?
I think this would be good.  IMO using this to count just feels more logical.

Not sure how hard that is implementation-wise though.

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkSampledCodec.cpp
File src/codec/SkSampledCodec.cpp (left):

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkSampledCodec.cp...
src/codec/SkSampledCodec.cpp:262: const int trueRowsDecoded = (rowsDecoded +
sampleY - 1) / sampleY;
Yes, yes, very glad to see this line of code get deleted.

[scroggo_chromium, 2016-10-10 18:15:05]

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkPngCodec.cpp
File src/codec/SkPngCodec.cpp (right):

https://codereview.chromium.org/2407543002/diff/1/src/codec/SkPngCodec.cpp#ne...
src/codec/SkPngCodec.cpp:545: // FIXME: Can we remove fLinesDecoded and just
rely on fRowsWrittenToOutput?
On 2016/10/10 17:19:58, msarett wrote:
> I think this would be good.  IMO using this to count just feels more logical.
> 
> Not sure how hard that is implementation-wise though.

Agreed. I don't think it's terribly hard, but it's not super straightforward,
either. My plan is to land this first and then follow-up with a change to
eliminate fLinesDecoded. It may mean reinterpreting what SkSampler::rowNeeded
expects, and I'd like to keep all of that separate from this change.

[scroggo_chromium, 2016-10-10 18:15:08]

The CQ bit was checked by scroggo@chromium.org

[scroggo_chromium, 2016-10-10 18:15:09]

The patchset sent to the CQ was uploaded after l-g-t-m from msarett@google.com
Link to the patchset: https://codereview.chromium.org/2407543002/#ps40001
(title: "Use fRowsWrittenToOutput in decodeAllRows (fix rebase issues)")

[commit-bot: I haz the power, 2016-10-10 18:15:12]

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, 2016-10-10 18:35:02]

Description was changed from

==========
Simplify rowsDecoded returned by incrementalDecode

When sampling, we previously had to figure out the number of rows that
were written to the output based on the value reported by
incrementalDecode. (We also messed up the first time - see the fix in
crrev.com/2343153003.)

Instead, make incrementalDecode report the actual number of rows
written to. This can be provided directly to fill.

Make SkPngCodec report the correct number of rows, by incrementing its
count when it actually writes to the destination.

This also will simplify my in progress GIF change.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2407543002
==========

to

==========
Simplify rowsDecoded returned by incrementalDecode

When sampling, we previously had to figure out the number of rows that
were written to the output based on the value reported by
incrementalDecode. (We also messed up the first time - see the fix in
crrev.com/2343153003.)

Instead, make incrementalDecode report the actual number of rows
written to. This can be provided directly to fill.

Make SkPngCodec report the correct number of rows, by incrementing its
count when it actually writes to the destination.

This also will simplify my in progress GIF change.
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2407543002

Committed:
https://skia.googlesource.com/skia/+/ff9f7bbef6fdbd2ae7965ff18981aa8df33abd96
==========

[commit-bot: I haz the power, 2016-10-10 18:35:03]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/ff9f7bbef6fdbd2ae7965ff18981aa8df33abd96