Remove V8_WARN_UNUSED_RESULT for simple getters.

src/platform/semaphore.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 62 matching lines @@
   bool WaitFor(const TimeDelta& rel_time) V8_WARN_UNUSED_RESULT;
 
 #if V8_OS_MACOSX
   typedef semaphore_t NativeHandle;
 #elif V8_OS_POSIX
   typedef sem_t NativeHandle;
 #elif V8_OS_WIN
   typedef HANDLE NativeHandle;
 #endif
 
-  NativeHandle& native_handle() V8_WARN_UNUSED_RESULT {
+  NativeHandle& native_handle() {
     return native_handle_;
   }
-  const NativeHandle& native_handle() const V8_WARN_UNUSED_RESULT {
+  const NativeHandle& native_handle() const {
     return native_handle_;
   }
 
  private:
   NativeHandle native_handle_;
 
   DISALLOW_COPY_AND_ASSIGN(Semaphore);
 };
 
 
@@ skipping 20 matching lines @@
       Semaphore,
       CreateSemaphoreTrait<N>,
       ThreadSafeInitOnceTrait>::type type;
 };
 
 #define LAZY_SEMAPHORE_INITIALIZER LAZY_DYNAMIC_INSTANCE_INITIALIZER
 
 } }  // namespace v8::internal
 
 #endif  // V8_PLATFORM_SEMAPHORE_H_