Fix Sky not to crash when clicking the Home button.

sky/shell/android/org/domokit/sky/shell/SkyActivity.java

Index: sky/shell/android/org/domokit/sky/shell/SkyActivity.java
diff --git a/sky/shell/android/org/domokit/sky/shell/SkyActivity.java b/sky/shell/android/org/domokit/sky/shell/SkyActivity.java
index 47480222d631d8d1010aa41565d32158ee3ef8fc..1ad89a292619eac74a2dc2755ebe033b2d8fa2ca 100644
--- a/sky/shell/android/org/domokit/sky/shell/SkyActivity.java
+++ b/sky/shell/android/org/domokit/sky/shell/SkyActivity.java
@@ -39,13 +39,13 @@ public class SkyActivity extends Activity {
     }
 
     /**
-     * @see android.app.Activity#onStop()
+     * @see android.app.Activity#onDestroy()
      */
     @Override
-    protected void onStop() {
+    protected void onDestroy() {
         // Do we need to shut down Sky too?
         mTracingController.stop();
-        super.onStop();
+        super.onDestroy();
     }
 
     public void loadUrl(String url) {