Convert SkRefCnt to std::atomic.

tests/TLSTest.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
+#include "SkAtomics.h"
 #include "SkGraphics.h"
 #include "SkPaint.h"
 #include "SkTLS.h"
 #include "SkThreadUtils.h"
 #include "Test.h"
 
 static void thread_main(void*) {
     SkGraphics::SetTLSFontCacheLimit(1 * 1024 * 1024);
 
     const char text[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
@@ skipping 53 matching lines @@
     // TODO: Disabled for now to work around
     // http://code.google.com/p/skia/issues/detail?id=619
     // ('flaky segfault in TLS test on Shuttle_Ubuntu12 buildbots')
     if( false ) test_threads(&thread_main);
 
     // Test to ensure that at thread destruction, TLS destructors
     // have been called.
     test_threads(&testTLSDestructor);
     REPORTER_ASSERT(reporter, 0 == gCounter);
 }