Fabric: Introducing -[RCTComponentViewProtocol componentHandle]

Summary: The new method in the protocol enforces view component classes to expose a component handle of the component that the view component represents. That will allow us to wire up those classes with shadow views in runtime explicitly and in a much more performant way than it is now.

Reviewed By: mdvacca

Differential Revision: D13114663

fbshipit-source-id: 853187d978aab200f85719d9c1d9fea2e3ad4e55

React/Fabric/Mounting/ComponentViews/Switch/RCTSwitchComponentView.mm

@@ -9,6 +9,7 @@
 
 #import <react/components/switch/SwitchEventEmitter.h>
 #import <react/components/switch/SwitchProps.h>
+#import <react/components/switch/SwitchShadowNode.h>
 
 using namespace facebook::react;
 
@@ -37,6 +38,13 @@ using namespace facebook::react;
   return self;
 }
 
+#pragma mark - RCTComponentViewProtocol
+
++ (ComponentHandle)componentHandle
+{
+  return SwitchShadowNode::Handle();
+}
+
 - (void)updateProps:(SharedProps)props oldProps:(SharedProps)oldProps
 {
   const auto &oldSwitchProps = *std::static_pointer_cast<const SwitchProps>(oldProps ?: _props);