Re-introduce UIImplementationProvider

Summary: UIImplementationProvider was removed as part of D8650376, this was a breaking change that caused problems in OSS. This diff introduces the concept of a deprecated UIImplementationProvider again to allow OSS community to upgrade to latest version of RN.

Reviewed By: achen1

Differential Revision: D10456317

fbshipit-source-id: 6817629524f927dfcb5ebc054dbfd983877b7606

ReactAndroid/src/main/java/com/facebook/react/ReactNativeHost.java

@@ -15,6 +15,7 @@ import com.facebook.react.bridge.ReactMarker;
 import com.facebook.react.bridge.ReactMarkerConstants;
 import com.facebook.react.common.LifecycleState;
 import com.facebook.react.devsupport.RedBoxHandler;
+import com.facebook.react.uimanager.UIImplementationProvider;
 import java.util.List;
 import javax.annotation.Nullable;
 
@@ -70,6 +71,7 @@ public abstract class ReactNativeHost {
       .setUseDeveloperSupport(getUseDeveloperSupport())
       .setRedBoxHandler(getRedBoxHandler())
       .setJavaScriptExecutorFactory(getJavaScriptExecutorFactory())
+      .setUIImplementationProvider(getUIImplementationProvider())
       .setJSIModulesPackage(getJSIModulePackage())
       .setInitialLifecycleState(LifecycleState.BEFORE_CREATE);
 
@@ -107,6 +109,16 @@ public abstract class ReactNativeHost {
     return mApplication;
   }
 
+  /**
+   * Get the {@link UIImplementationProvider} to use. Override this method if you want to use a
+   * custom UI implementation.
+   *
+   * Note: this is very advanced functionality, in 99% of cases you don't need to override this.
+   */
+  protected UIImplementationProvider getUIImplementationProvider() {
+    return new UIImplementationProvider();
+  }
+
   protected @Nullable
   JSIModulePackage getJSIModulePackage() {
     return null;