Re-land 714393002 after fixing android build.

sky/engine/wtf/Atomics.h

Index: sky/engine/wtf/Atomics.h
diff --git a/sky/engine/wtf/Atomics.h b/sky/engine/wtf/Atomics.h
index aaad9c9e90cbe954fd9d30ec7a89488822201298..343d306596389e3167c8ac191da810e6d052c7ac 100644
--- a/sky/engine/wtf/Atomics.h
+++ b/sky/engine/wtf/Atomics.h
@@ -35,51 +35,12 @@
 
 #include <stdint.h>
 
-#if COMPILER(MSVC)
-#include <windows.h>
-#endif
-
 #if defined(THREAD_SANITIZER)
 #include <sanitizer/tsan_interface_atomic.h>
 #endif
 
 namespace WTF {
 
-#if COMPILER(MSVC)
-
-// atomicAdd returns the result of the addition.
-ALWAYS_INLINE int atomicAdd(int volatile* addend, int increment)
-{
-    return InterlockedExchangeAdd(reinterpret_cast<long volatile*>(addend), static_cast<long>(increment)) + increment;
-}
-
-// atomicSubtract returns the result of the subtraction.
-ALWAYS_INLINE int atomicSubtract(int volatile* addend, int decrement)
-{
-    return InterlockedExchangeAdd(reinterpret_cast<long volatile*>(addend), static_cast<long>(-decrement)) - decrement;
-}
-
-ALWAYS_INLINE int atomicIncrement(int volatile* addend) { return InterlockedIncrement(reinterpret_cast<long volatile*>(addend)); }
-ALWAYS_INLINE int atomicDecrement(int volatile* addend) { return InterlockedDecrement(reinterpret_cast<long volatile*>(addend)); }
-
-ALWAYS_INLINE int64_t atomicIncrement(int64_t volatile* addend) { return InterlockedIncrement64(reinterpret_cast<long long volatile*>(addend)); }
-ALWAYS_INLINE int64_t atomicDecrement(int64_t volatile* addend) { return InterlockedDecrement64(reinterpret_cast<long long volatile*>(addend)); }
-
-ALWAYS_INLINE int atomicTestAndSetToOne(int volatile* ptr)
-{
-    int ret = InterlockedExchange(reinterpret_cast<long volatile*>(ptr), 1);
-    ASSERT(!ret || ret == 1);
-    return ret;
-}
-
-ALWAYS_INLINE void atomicSetOneToZero(int volatile* ptr)
-{
-    ASSERT(*ptr == 1);
-    InterlockedExchange(reinterpret_cast<long volatile*>(ptr), 0);
-}
-
-#else
-
 // atomicAdd returns the result of the addition.
 ALWAYS_INLINE int atomicAdd(int volatile* addend, int increment) { return __sync_add_and_fetch(addend, increment); }
 // atomicSubtract returns the result of the subtraction.
@@ -103,7 +64,6 @@ ALWAYS_INLINE void atomicSetOneToZero(int volatile* ptr)
     ASSERT(*ptr == 1);
     __sync_lock_release(ptr);
 }
-#endif
 
 #if defined(THREAD_SANITIZER)
 ALWAYS_INLINE void releaseStore(volatile int* ptr, int value)
@@ -129,14 +89,7 @@ ALWAYS_INLINE unsigned acquireLoad(volatile const unsigned* ptr)
 
 #if CPU(X86) || CPU(X86_64)
 // Only compiler barrier is needed.
-#if COMPILER(MSVC)
-// Starting from Visual Studio 2005 compiler guarantees acquire and release
-// semantics for operations on volatile variables. See MSDN entry for
-// MemoryBarrier macro.
-#define MEMORY_BARRIER()
-#else
 #define MEMORY_BARRIER() __asm__ __volatile__("" : : : "memory")
-#endif
 #elif CPU(ARM) && (OS(LINUX) || OS(ANDROID))
 // On ARM __sync_synchronize generates dmb which is very expensive on single
 // core devices which don't actually need it. Avoid the cost by calling into