[ReactNative] Allow JS know its URL

React/Base/RCTBridge.h

@@ -88,6 +88,11 @@ static const char *__rct_import_##module##_##method##__ = #module"."#method;
                              url:(NSURL *)url
                       onComplete:(RCTJavaScriptCompleteBlock)onComplete;
 
+/**
+ * URL of the script that was loaded into the bridge.
+ */
+@property (nonatomic, copy, readonly) NSURL *bundleURL;
+
 @property (nonatomic, strong) Class executorClass;
 
 /**