Suppress warning when checking for JSGlobalContextSetName

Summary: This API is defined only on iOS 8 and newer. There is a warning that the function is defined when checking if it exists since it is always defined in the iOS 8 SDK but not necessarily on iOS 7 phones. Use pragmas to silence the warning. Closes facebook#2475 Reviewed By: @​trunkagent, @vjeux Differential Revision: D2443432 Pulled By: @tadeuzagallo

Author: ide

React/Executors/RCTContextExecutor.m

@@ -587,7 +587,10 @@ - (void)injectJSONText:(NSString *)script
 
 RCT_EXPORT_METHOD(setContextName:(nonnull NSString *)name)
 {
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wtautological-pointer-compare"
  if (JSGlobalContextSetName != NULL) {
+#pragma clang diagnostic pop
  JSStringRef JSName = JSStringCreateWithCFString((__bridge CFStringRef)name);
  JSGlobalContextSetName(_context.ctx, JSName);
  JSStringRelease(JSName);