Simplify SkInstCnt

Simplify SkInstCnt

This code requires fewer macros to use it (just one), has less code in macro
definitions, and has simpler synchronization code (just atomic ints, no SkOnce,
no SkMutex, etc.)

A minor downside, we lose indentation and reverse-ordering in the final report:
  Leaked SkRefCntBase: 7
     Leaked SkFontMgr: 1
     Leaked SkWeakRefCnt: 1
         Leaked SkTypeface: 1
     Leaked SkFlattenable: 3
         Leaked SkXfermode: 3
     Leaked SkPathRef: 1
     Leaked SkPixelRef: 1
         Leaked SkMallocPixelRef: 1
becomes
  Leaked SkXfermode: 3
  Leaked SkMallocPixelRef: 1
  Leaked SkPixelRef: 1
  Leaked SkPathRef: 1
  Leaked SkFlattenable: 3
  Leaked SkTypeface: 1
  Leaked SkWeakRefCnt: 1
  Leaked SkFontMgr: 1
  Leaked SkRefCntBase: 7

This is motivated by wanting to land https://codereview.chromium.org/806473006/, 
which makes sure all static use of SkOnce are in global scope.  The current 
implementation of SkInstCnt uses them in function scope, which isn't safe.
BUG=skia:

No public API changes.
TBR=reed@google.com

Committed: https://skia.googlesource.com/skia/+/6f07665768dc84453316e7b2bbd6049576764cb1

[mtklein, 2015-01-12 19:25:12]

mtklein@google.com changed reviewers:
+ mtklein@google.com, robertphillips@google.com

[robertphillips, 2015-01-13 14:21:37]

lgtm + nits

https://codereview.chromium.org/841263004/diff/1/include/core/SkInstCnt.h
File include/core/SkInstCnt.h (right):

https://codereview.chromium.org/841263004/diff/1/include/core/SkInstCnt.h#new...
include/core/SkInstCnt.h:50: SkInstCount(const SkInstCount&) { Inc(); }
== ?

https://codereview.chromium.org/841263004/diff/1/src/core/SkInstCnt.cpp
File src/core/SkInstCnt.cpp (right):

https://codereview.chromium.org/841263004/diff/1/src/core/SkInstCnt.cpp#newcode9
src/core/SkInstCnt.cpp:9: 
Make this positive and eliminate the #else ?

[mtklein, 2015-01-13 15:26:39]

https://codereview.chromium.org/841263004/diff/1/include/core/SkInstCnt.h
File include/core/SkInstCnt.h (right):

https://codereview.chromium.org/841263004/diff/1/include/core/SkInstCnt.h#new...
include/core/SkInstCnt.h:50: SkInstCount(const SkInstCount&) { Inc(); }
On 2015/01/13 14:21:36, robertphillips wrote:
> == ?

Done.

https://codereview.chromium.org/841263004/diff/1/src/core/SkInstCnt.cpp
File src/core/SkInstCnt.cpp (right):

https://codereview.chromium.org/841263004/diff/1/src/core/SkInstCnt.cpp#newcode9
src/core/SkInstCnt.cpp:9: 
On 2015/01/13 14:21:36, robertphillips wrote:
> Make this positive and eliminate the #else ?

Done.

[mtklein, 2015-01-13 15:26:42]

The CQ bit was checked by mtklein@google.com

[mtklein, 2015-01-13 15:26:56]

The CQ bit was unchecked by mtklein@google.com

[mtklein, 2015-01-13 15:27:13]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2015-01-13 15:28:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/841263004/20001

[commit-bot: I haz the power, 2015-01-13 15:29:50]

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

[commit-bot: I haz the power, 2015-01-13 15:29:50]

Try jobs failed on following builders:
  Test-Ubuntu13.10-GCE-NoGPU-x86_64-Debug-Trybot on client.skia
(http://build.chromium.org/p/client.skia/builders/Test-Ubuntu13.10-GCE-NoGPU-x...)

[mtklein, 2015-01-13 16:11:27]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2015-01-13 16:12:30]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/841263004/40001

[commit-bot: I haz the power, 2015-01-13 16:22:47]

Committed patchset #3 (id:40001) as
https://skia.googlesource.com/skia/+/6f07665768dc84453316e7b2bbd6049576764cb1