2 files changed, 25 insertions, 13 deletions
diff --git a/chrome/browser/extensions/extension_message_service.cc b/chrome/browser/extensions/extension_message_service.cc
index f200c5b..74e2757 100755
--- a/chrome/browser/extensions/extension_message_service.cc
+++ b/chrome/browser/extensions/extension_message_service.cc
@@ -129,15 +129,19 @@ void ExtensionMessageService::PostMessageFromRenderer(
   dest->Send(new ViewMsg_ExtensionHandleMessage(message, source_port_id));
 }
 
-void ExtensionMessageService::RendererReady(ResourceMessageFilter* renderer) {
+void ExtensionMessageService::RendererReady(ResourceMessageFilter* filter) {
   AutoLock lock(renderers_lock_);
-  DCHECK(renderers_.find(renderer->GetProcessId()) == renderers_.end());
-  renderers_[renderer->GetProcessId()] = renderer;
-
-  NotificationService::current()->AddObserver(
-      this,
-      NotificationType::RESOURCE_MESSAGE_FILTER_SHUTDOWN,
-      Source<ResourceMessageFilter>(renderer));
+  DCHECK(renderers_.find(filter->GetProcessId()) == renderers_.end());
+  renderers_[filter->GetProcessId()] = filter;
+
+  // Only observe this filter if we haven't seen it before.
+  if (filters_.find(filter) == filters_.end()) {
+    filters_.insert(filter);
+    NotificationService::current()->AddObserver(
+        this,
+        NotificationType::RESOURCE_MESSAGE_FILTER_SHUTDOWN,
+        Source<ResourceMessageFilter>(filter));
+  }
 }
 
 void ExtensionMessageService::Observe(NotificationType type,
@@ -161,9 +165,13 @@ void ExtensionMessageService::Observe(NotificationType type,
       channels_.erase(current);
   }
 
-  NotificationService::current()->RemoveObserver(
-      this,
-      NotificationType::RESOURCE_MESSAGE_FILTER_SHUTDOWN,
-      Source<ResourceMessageFilter>(filter));
+  std::set<ResourceMessageFilter*>::iterator fit = filters_.find(filter);
+  if (fit != filters_.end()) {
+    filters_.erase(fit);
+    NotificationService::current()->RemoveObserver(
+        this,
+        NotificationType::RESOURCE_MESSAGE_FILTER_SHUTDOWN,
+        source);
+  }
 }
 
diff --git a/chrome/browser/extensions/extension_message_service.h b/chrome/browser/extensions/extension_message_service.h
index 1fc3c51..1238338 100755
--- a/chrome/browser/extensions/extension_message_service.h
+++ b/chrome/browser/extensions/extension_message_service.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_SERVICE_H_
 
 #include <map>
+#include <set>
 #include <string>
 
 #include "base/lock.h"
@@ -53,7 +54,7 @@ class ExtensionMessageService : public NotificationObserver {
   // --- UI or IO thread:
 
   // Called to let us know that a renderer has been started.
-  void RendererReady(ResourceMessageFilter* port);
+  void RendererReady(ResourceMessageFilter* filter);
 
   // NotificationObserver interface.
   void Observe(NotificationType type,
@@ -89,6 +90,9 @@ class ExtensionMessageService : public NotificationObserver {
 
   // For generating unique channel IDs.
   int next_port_id_;
+
+  // For tracking the ResourceMessageFilters we are observing.
+  std::set<ResourceMessageFilter*> filters_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_SERVICE_H_