Remove V8_WARN_UNUSED_RESULT for simple getters.

src/platform/condition-variable.h

Index: src/platform/condition-variable.h
diff --git a/src/platform/condition-variable.h b/src/platform/condition-variable.h
index 43cc529deb510777f51c0bfc7f2f5feb9afef374..4d8a88aee79f084289cb7e4861f4a887f1690c43 100644
--- a/src/platform/condition-variable.h
+++ b/src/platform/condition-variable.h
@@ -105,10 +105,10 @@ class ConditionVariable V8_FINAL {
   };
 #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_;
   }