Test extension reloading behavior.

content/public/test/mock_render_process_host.h

Index: content/public/test/mock_render_process_host.h
diff --git a/content/public/test/mock_render_process_host.h b/content/public/test/mock_render_process_host.h
index 832c5245207b050c9eb2aa9e2bbafa717b90e4f4..f8ebc6de0ca2f1a80faaa3fa3e71de46be943bbf 100644
--- a/content/public/test/mock_render_process_host.h
+++ b/content/public/test/mock_render_process_host.h
@@ -117,12 +117,31 @@ class MockRenderProcessHostFactory : public RenderProcessHostFactory {
   // to remove it from |processes_| to prevent it from being deleted twice.
   void Remove(MockRenderProcessHost* host) const;
 
+  class Observer {
+   public:
+    Observer(MockRenderProcessHostFactory* factory);
+    virtual ~Observer();
+    virtual void OnRenderProcessHostCreated(MockRenderProcessHost*) {}
+    virtual void OnRenderProcessHostDestroyed(MockRenderProcessHost*) {}
+   private:
+    MockRenderProcessHostFactory* factory_;
+  };
+
+  void AddObserver(Observer* obs) {
+    observer_list_.AddObserver(obs);
+  }
+  void RemoveObserver(Observer* obs) {
+    observer_list_.RemoveObserver(obs);
+  }
+
  private:
   // A list of MockRenderProcessHosts created by this object. This list is used
   // for deleting all MockRenderProcessHosts that have not deleted by a test in
   // the destructor and prevent them from being leaked.
   mutable ScopedVector<MockRenderProcessHost> processes_;
 
+  mutable ObserverList<Observer> observer_list_;
+
   DISALLOW_COPY_AND_ASSIGN(MockRenderProcessHostFactory);
 };