Another fix

Reviewed By: benhiller

Differential Revision: D4185166

fbshipit-source-id: 940dbfbd65c94455979c7e88375784a5c68647a5

React/Executors/RCTJSCExecutor.mm

@@ -419,6 +419,8 @@ static NSThread *newJavaScriptThread(void)
       }
     };
 
+#ifdef RCT_DEV
+
     // Add toggles for JSC's sampling profiler, if the profiler is enabled
     if (self->_jscWrapper->JSSamplingProfilerEnabled()) {
         // Mark this thread as the main JS thread before starting profiling.
@@ -449,6 +451,7 @@ static NSThread *newJavaScriptThread(void)
       };
     }
 #endif
+#endif
 
 #if RCT_DEV
     RCTInstallJSCProfiler(self->_bridge, context.JSGlobalContextRef);