Deprecated RCTDidCreateNativeModules notification

Summary:
public

Thanks to the new lazy initialization system for modules, `RCTDidCreateNativeModules` no longer does what the name implies.

Previously, `RCTDidCreateNativeModules` was fired after all native modules had been initialized. Now, it simply fires each time the bridge is reloaded. Modules are created on demand when they are needed, so most of the assumptions about when `RCTDidCreateNativeModules` will fire are now incorrect.

This diff deprecates `RCTDidCreateNativeModules`, and adds a new notification, `RCTDidInitializeModuleNotification`, which fires each time a module a new module is instantiated.

If you need to access a module at any time you can just call `-[bridge moduleForClass:]` and the module will be instantiated on demand. If you want to access a module *only* after it has already been instantiated, you can use the `RCTDidInitializeModuleNotification` notification.

Reviewed By: tadeuzagallo

Differential Revision: D2755036

fb-gh-sync-id: 25bab6d5eb6fcd35d43125ac45908035eea01487

React/Profiler/RCTProfile.m

@@ -403,7 +403,7 @@ void RCTProfileInit(RCTBridge *bridge)
                               forMode:NSRunLoopCommonModes];
 
   [[NSNotificationCenter defaultCenter] postNotificationName:RCTProfileDidStartProfiling
-                                                      object:nil];
+                                                      object:bridge];
 }
 
 void RCTProfileEnd(RCTBridge *bridge, void (^callback)(NSString *))
@@ -417,7 +417,7 @@ void RCTProfileEnd(RCTBridge *bridge, void (^callback)(NSString *))
   OSAtomicAnd32Barrier(0, &RCTProfileProfiling);
 
   [[NSNotificationCenter defaultCenter] postNotificationName:RCTProfileDidEndProfiling
-                                                      object:nil];
+                                                      object:bridge];
 
   [RCTProfileDisplayLink invalidate];
   RCTProfileDisplayLink = nil;