Merge pull request #2955 from wjaykim/patch-1

fix(android): check null activity

android/src/main/java/com/brentvatne/exoplayer/ReactExoplayerView.java

@@ -573,6 +573,12 @@ class ReactExoplayerView extends FrameLayout implements
                                     return;
                                 }
                                     
+                                if (activity == null) {
+                                    Log.e("ExoPlayer Exception", "Failed to initialize Player!");
+                                    eventEmitter.error("Failed to initialize Player!", new Exception("Current Activity is null!"), "1001");
+                                    return;
+                                }
+
                                 // Initialize handler to run on the main thread
                                 activity.runOnUiThread(new Runnable() {
                                     public void run() {