Remove yet-unused 64-bit atomic hooks.

include/core/SkThread.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkThread_DEFINED
 #define SkThread_DEFINED
 
 #include "SkTypes.h"
 
 // SK_ATOMICS_PLATFORM_H must provide inline implementations for the following declarations.
 
 /** Atomically adds one to the int referenced by addr and returns the previous value.
  *  No additional memory barrier is required; this must act as a compiler barrier.
  */
 static int32_t sk_atomic_inc(int32_t* addr);
 static int64_t sk_atomic_inc(int64_t* addr);
 
 /** Atomically adds inc to the int referenced by addr and returns the previous value.
  *  No additional memory barrier is required; this must act as a compiler barrier.
  */
 static int32_t sk_atomic_add(int32_t* addr, int32_t inc);
-static int64_t sk_atomic_add(int64_t* addr, int64_t inc);
 
 /** Atomically subtracts one from the int referenced by addr and returns the previous value.
  *  This must act as a release (SL/S) memory barrier and as a compiler barrier.
  */
 static int32_t sk_atomic_dec(int32_t* addr);
-static int64_t sk_atomic_dec(int64_t* addr);
 
 /** Atomic compare and set.
  *  If *addr == before, set *addr to after and return true, otherwise return false.
  *  This must act as a release (SL/S) memory barrier and as a compiler barrier.
  */
 static bool sk_atomic_cas(int32_t* addr, int32_t before, int32_t after);
-static bool sk_atomic_cas(int64_t* addr, int64_t before, int64_t after);
 
 /** If sk_atomic_dec does not act as an acquire (L/SL) barrier,
  *  this must act as an acquire (L/SL) memory barrier and as a compiler barrier.
  */
 static void sk_membar_acquire__after_atomic_dec();
 
 /** If sk_atomic_conditional_inc does not act as an acquire (L/SL) barrier,
  *  this must act as an acquire (L/SL) memory barrier and as a compiler barrier.
  */
 static void sk_membar_acquire__after_atomic_conditional_inc();
@@ skipping 89 matching lines @@
         SkASSERT(fMutex);
         fMutex->assertHeld();
     }
 
 private:
     SkBaseMutex* fMutex;
 };
 #define SkAutoMutexAcquire(...) SK_REQUIRE_LOCAL_VAR(SkAutoMutexAcquire)
 
 #endif