Add SkRacy

Add SkRacy

SkRacy<T> is a zero-overhead wrapper for a T, except it also
silences race warnings when TSAN is running.

Here we apply in several classes.  In SkMatrix and SkPathRef,
we use it to opportunistically cache some idempotent work.

In SkPixelRef, we wrap the genIDs.  We think the worst that
can happen here is we'll increment the global next-genID a
few times instead of once when we go to get another ID.

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/d5e3e6ae1b3434ad1158f441902ff65f1eeaa3a7

CQ_EXTRA_TRYBOTS=tryserver.skia:Canary-Chrome-Ubuntu13.10-Ninja-x86_64-ToT-Trybot,Canary-Chrome-Win7-Ninja-x86-SharedLib_ToT-Trybot,Test-Ubuntu13.10-GCE-NoGPU-x86_64-Release-TSAN-Trybot

Committed: https://skia.googlesource.com/skia/+/0b544ae222aab1c5d9122a8dfe2800451b31d979

[reed1, 2014-07-08 19:08:55]

lgtm

https://codereview.chromium.org/371363004/diff/110001/include/core/SkDynamicA...
File include/core/SkDynamicAnnotations.h (right):

https://codereview.chromium.org/371363004/diff/110001/include/core/SkDynamicA...
include/core/SkDynamicAnnotations.h:61: class SkRacy {
nit: SkTRacy

[mtklein, 2014-07-08 19:14:23]

https://codereview.chromium.org/371363004/diff/110001/include/core/SkDynamicA...
File include/core/SkDynamicAnnotations.h (right):

https://codereview.chromium.org/371363004/diff/110001/include/core/SkDynamicA...
include/core/SkDynamicAnnotations.h:61: class SkRacy {
On 2014/07/08 19:08:54, reed1 wrote:
> nit: SkTRacy

Done.

[mtklein, 2014-07-08 19:14:39]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-07-08 19:15:08]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/mtklein@chromium.org/371363004/130001

[commit-bot: I haz the power, 2014-07-08 19:30:45]

Change committed as d5e3e6ae1b3434ad1158f441902ff65f1eeaa3a7

[mtklein, 2014-07-08 21:05:40]

A revert of this CL has been created in
https://codereview.chromium.org/377693005/ by mtklein@google.com.

The reason for reverting is: hidden symbol 'AnnotateBenignRaceSized' in
obj/base/third_party/dynamic_annotations/libdynamic_annotations.a(obj/base/third_party/dynamic_annotations/dynamic_annotations.dynamic_annotations.o)
is referenced by DSO lib/libblink_platform.so.

[mtklein, 2014-07-08 21:47:56]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2014-07-08 21:48:53]

CQ is trying da patch. Follow status at
 https://skia-tree-status.appspot.com/cq/mtklein@chromium.org/371363004/150001

[commit-bot: I haz the power, 2014-07-09 02:37:52]

Change committed as 0b544ae222aab1c5d9122a8dfe2800451b31d979