Introduce RenderProcessHostObserver, use it in its first client.

content/public/test/mock_render_process_host.cc

Index: content/public/test/mock_render_process_host.cc
diff --git a/content/public/test/mock_render_process_host.cc b/content/public/test/mock_render_process_host.cc
index 20f44cca3690ebfc4bf880aa373d32fdea50029e..50f863d5a5f95830bb7f32617d7730102c013368 100644
--- a/content/public/test/mock_render_process_host.cc
+++ b/content/public/test/mock_render_process_host.cc
@@ -19,15 +19,15 @@
 
 namespace content {
 
-MockRenderProcessHost::MockRenderProcessHost(
-    BrowserContext* browser_context)
-        : transport_dib_(NULL),
-          bad_msg_count_(0),
-          factory_(NULL),
-          id_(ChildProcessHostImpl::GenerateChildProcessUniqueId()),
-          browser_context_(browser_context),
-          prev_routing_id_(0),
-          fast_shutdown_started_(false) {
+MockRenderProcessHost::MockRenderProcessHost(BrowserContext* browser_context)
+    : transport_dib_(NULL),
+      bad_msg_count_(0),
+      factory_(NULL),
+      id_(ChildProcessHostImpl::GenerateChildProcessUniqueId()),
+      browser_context_(browser_context),
+      prev_routing_id_(0),
+      fast_shutdown_started_(false),
+      deletion_callback_called_(false) {
   // Child process security operations can't be unit tested unless we add
   // ourselves as an existing child process.
   ChildProcessSecurityPolicyImpl::GetInstance()->Add(GetID());
@@ -36,6 +36,12 @@ MockRenderProcessHost::MockRenderProcessHost(
 }
 
 MockRenderProcessHost::~MockRenderProcessHost() {
+  if (!deletion_callback_called_) {
+    FOR_EACH_OBSERVER(RenderProcessHostObserver,
+                      observers_,
+                      RenderProcessHostDestroyed(this));
+  }
+
   ChildProcessSecurityPolicyImpl::GetInstance()->Remove(GetID());
   delete transport_dib_;
   if (factory_)
@@ -67,6 +73,15 @@ void MockRenderProcessHost::RemoveRoute(int32 routing_id) {
   Cleanup();
 }
 
+void MockRenderProcessHost::AddObserver(RenderProcessHostObserver* observer) {
+  observers_.AddObserver(observer);
+}
+
+void MockRenderProcessHost::RemoveObserver(
+    RenderProcessHostObserver* observer) {
+  observers_.RemoveObserver(observer);
+}
+
 bool MockRenderProcessHost::WaitForBackingStoreMsg(
     int render_widget_id,
     const base::TimeDelta& max_delay,
@@ -169,6 +184,10 @@ bool MockRenderProcessHost::IgnoreInputEvents() const {
 
 void MockRenderProcessHost::Cleanup() {
   if (listeners_.IsEmpty()) {
+    FOR_EACH_OBSERVER(RenderProcessHostObserver,
+                      observers_,
+                      RenderProcessHostDestroyed(this));
+    deletion_callback_called_ = true;
     NotificationService::current()->Notify(
         NOTIFICATION_RENDERER_PROCESS_TERMINATED,
         Source<RenderProcessHost>(this),