Use RCTDevLoadingView in a sample app

Reviewed By: javache

Differential Revision: D4985384

fbshipit-source-id: 1d5a33a6746010d3cf4ac524468af21bb9599f3e

Author: fromcelticpark

React/DevSupport/RCTDevLoadingView.h

@@ -14,6 +14,8 @@
 @interface RCTDevLoadingView : NSObject <RCTBridgeModule>
 
 + (void)setEnabled:(BOOL)enabled;
+- (void)showWithURL:(NSURL *)URL;
 - (void)updateProgress:(RCTLoadingProgress *)progress;
+- (void)hide;
 
 @end

React/DevSupport/RCTDevLoadingView.m

@@ -161,7 +161,9 @@ @implementation RCTDevLoadingView
 
 + (NSString *)moduleName { return nil; }
 + (void)setEnabled:(BOOL)enabled { }
-- (void)updateProgress:(RCTLoadingProgress *)progress {}
+- (void)showWithURL:(NSURL *)URL { }
+- (void)updateProgress:(RCTLoadingProgress *)progress { }
+- (void)hide { }
 
 @end