Fix caching of nvpr glyphs

Updates nvpr text blobs to not store a direct reference to the
per-glyph GPU path object, but rather store a key for looking it up in
the resource cache. This allows the cache to purge glyphs when needed.
Also indirectly fixes a memory leak that was introduced with nvpr text
blobs.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/8585dd26bf74edf26a1cd1c31699c03347f78937

[Chris Dalton, 2015-10-06 16:31:53]

cdalton@nvidia.com changed reviewers:
+ bsalomon@google.com, egdaniel@google.com

[Chris Dalton, 2015-10-06 16:31:54]

This fixes the immediate memory leak.

Although, I think there still is an issue that these cached blobs keep a
reference to the GrPathRange, so even if the resource cache purges it, that
memory sticks around as long as the cached blob. Is there some sort of mechanism
for a weak ref to an object in the resource cache?

[bsalomon, 2015-10-06 16:43:04]

On 2015/10/06 16:31:54, Chris Dalton wrote:
> This fixes the immediate memory leak.
> 
> Although, I think there still is an issue that these cached blobs keep a
> reference to the GrPathRange, so even if the resource cache purges it, that
> memory sticks around as long as the cached blob. Is there some sort of
mechanism
> for a weak ref to an object in the resource cache?

Keeping a ref will prevent the resource from being purged by the cache. In
general, we don't keep long-lived refs on GPU resources in order to give the
cache a chance to free them (aside from some legacy cases that are being cleaned
up). A cache key is a weak ref in a sense.

[Chris Dalton, 2015-10-07 14:20:43]

This patchset also fixes the glyph caching issue. It ended up being more
complicated than I expected, but let me know what you think.

[bsalomon, 2015-10-07 14:30:54]

mostly looks good, some small things noted inline.

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrPathRange.h
File src/gpu/GrPathRange.h (right):

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrPathRange.h#n...
src/gpu/GrPathRange.h:152: const uint32_t fUniqueID;
All GrGpuResources share a uniqueID implementation, gettable via getUniqueID().

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrStencilAndCov...
File src/gpu/GrStencilAndCoverTextContext.cpp (right):

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrStencilAndCov...
src/gpu/GrStencilAndCoverTextContext.cpp:341: builder.finish();
builder calls finish in it's destructor. You only need an explicit call if
you're using the key before the builder is out of scope (and you'd hit an assert
if you did it wrong).

[Chris Dalton, 2015-10-07 15:46:20]

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrPathRange.h
File src/gpu/GrPathRange.h (right):

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrPathRange.h#n...
src/gpu/GrPathRange.h:152: const uint32_t fUniqueID;
On 2015/10/07 14:30:54, bsalomon wrote:
> All GrGpuResources share a uniqueID implementation, gettable via
getUniqueID().

Done.

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrStencilAndCov...
File src/gpu/GrStencilAndCoverTextContext.cpp (right):

https://codereview.chromium.org/1374853004/diff/20001/src/gpu/GrStencilAndCov...
src/gpu/GrStencilAndCoverTextContext.cpp:341: builder.finish();
On 2015/10/07 14:30:54, bsalomon wrote:
> builder calls finish in it's destructor. You only need an explicit call if
> you're using the key before the builder is out of scope (and you'd hit an
assert
> if you did it wrong).

Done.

[bsalomon, 2015-10-07 15:54:00]

lgtm

[Chris Dalton, 2015-10-07 16:27:38]

The CQ bit was checked by cdalton@nvidia.com

[commit-bot: I haz the power, 2015-10-07 16:27:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1374853004/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1374853004/40001

[commit-bot: I haz the power, 2015-10-07 16:28:31]

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

[commit-bot: I haz the power, 2015-10-07 16:28:32]

Try jobs failed on following builders:
  Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug-Trybot on client.skia (JOB_FAILED,
http://build.chromium.org/p/client.skia/builders/Test-Ubuntu-GCC-GCE-CPU-AVX2...)
  Build-Ubuntu-GCC-x86_64-Release-Trybot on client.skia.compile (JOB_FAILED,
http://build.chromium.org/p/client.skia.compile/builders/Build-Ubuntu-GCC-x86...)

[bsalomon, 2015-10-08 14:31:47]

On 2015/10/07 16:28:32, commit-bot: I haz the power wrote:
> Try jobs failed on following builders:
>   Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Debug-Trybot on client.skia (JOB_FAILED,
>
http://build.chromium.org/p/client.skia/builders/Test-Ubuntu-GCC-GCE-CPU-AVX2...)
>   Build-Ubuntu-GCC-x86_64-Release-Trybot on client.skia.compile (JOB_FAILED,
>
http://build.chromium.org/p/client.skia.compile/builders/Build-Ubuntu-GCC-x86...)

Hey Chris, looks like the patch failed to apply, probably a simple rebase
needed. Can you rebase and try to land?

[Chris Dalton, 2015-10-08 14:45:27]

The CQ bit was checked by cdalton@nvidia.com

[Chris Dalton, 2015-10-08 14:45:27]

The patchset sent to the CQ was uploaded after l-g-t-m from bsalomon@google.com
Link to the patchset: https://codereview.chromium.org/1374853004/#ps60001
(title: "rebase")

[commit-bot: I haz the power, 2015-10-08 14:45:33]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1374853004/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1374853004/60001

[commit-bot: I haz the power, 2015-10-08 14:46:26]

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

[commit-bot: I haz the power, 2015-10-08 14:46:26]

Try jobs failed on following builders:
  Build-Ubuntu-Clang-x86_64-Debug-Trybot on client.skia.compile (JOB_FAILED,
http://build.chromium.org/p/client.skia.compile/builders/Build-Ubuntu-Clang-x...)

[Chris Dalton, 2015-10-08 14:49:01]

The CQ bit was checked by cdalton@nvidia.com

[Chris Dalton, 2015-10-08 14:49:01]

The patchset sent to the CQ was uploaded after l-g-t-m from bsalomon@google.com
Link to the patchset: https://codereview.chromium.org/1374853004/#ps80001
(title: "Accidental build error")

[commit-bot: I haz the power, 2015-10-08 14:49:18]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1374853004/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1374853004/80001

[commit-bot: I haz the power, 2015-10-08 14:51:48]

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

[commit-bot: I haz the power, 2015-10-08 14:51:49]

Try jobs failed on following builders:
  Build-Win-MSVC-x86_64-Debug-Trybot on client.skia.compile (JOB_FAILED,
http://build.chromium.org/p/client.skia.compile/builders/Build-Win-MSVC-x86_6...)

[Chris Dalton, 2015-10-08 14:57:04]

The CQ bit was checked by cdalton@nvidia.com

[Chris Dalton, 2015-10-08 14:57:04]

The patchset sent to the CQ was uploaded after l-g-t-m from bsalomon@google.com
Link to the patchset: https://codereview.chromium.org/1374853004/#ps100001
(title: "MSVC warnings")

[commit-bot: I haz the power, 2015-10-08 14:57:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1374853004/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1374853004/100001

[commit-bot: I haz the power, 2015-10-08 15:04:13]

Committed patchset #6 (id:100001) as
https://skia.googlesource.com/skia/+/8585dd26bf74edf26a1cd1c31699c03347f78937