Add log output to rule out that multiple react context creation are responsible for increased mem / image not loading in CTScan

Reviewed By: @​krangarajan

Differential Revision: D2495435

Author: olinotteghem

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

@@ -492,6 +492,7 @@ private void tearDownReactContext(ReactContext reactContext) {
   private ReactApplicationContext createReactContext(
       JavaScriptExecutor jsExecutor,
       JSBundleLoader jsBundleLoader) {
+    FLog.i(ReactConstants.TAG, "Creating react context.");
     NativeModuleRegistry.Builder nativeRegistryBuilder = new NativeModuleRegistry.Builder();
     JavaScriptModulesConfig.Builder jsModulesBuilder = new JavaScriptModulesConfig.Builder();