fixes bug 246085 "fire category manager notifications on the main thread only" patch by chpe@gnome.org, r=dougt, sr=darin

xpcom/build/nsXPCOM.h

@@ -384,7 +384,7 @@ NS_Free(void* ptr);
  * This topic is notified when an entry was added to a category in the
  * category manager. The subject of the notification will be the name of
  * the added entry as an nsISupportsCString, and the data will be the
- * name of the category.
+ * name of the category. The notification will occur on the main thread.
  *
  * @status FROZEN
  */
@@ -395,7 +395,7 @@ NS_Free(void* ptr);
  * This topic is notified when an entry was removed from a category in the
  * category manager. The subject of the notification will be the name of
  * the removed entry as an nsISupportsCString, and the data will be the
- * name of the category.
+ * name of the category. The notification will occur on the main thread.
  *
  * @status FROZEN
  */
@@ -406,6 +406,7 @@ NS_Free(void* ptr);
  * This topic is notified when an a category was cleared in the category
  * manager. The subject of the notification will be the category manager,
  * and the data will be the name of the cleared category.
+ * The notification will occur on the main thread.
  *
  * @status FROZEN
  */

xpcom/components/nsCategoryManager.cpp

@@ -58,6 +58,7 @@
 #include "nsCRT.h"
 #include "nsQuickSort.h"
 #include "nsEnumeratorUtils.h"
+#include "nsIProxyObjectManager.h"
 
 class nsIComponentLoaderManager;
 
@@ -530,7 +531,15 @@ nsCategoryManager::NotifyObservers( const char *aTopic,
     (do_GetService("@mozilla.org/observer-service;1"));
   if (!observerService)
     return;
- 
+
+  nsCOMPtr<nsIObserverService> obsProxy;
+  NS_GetProxyForObject(NS_UI_THREAD_EVENTQ,
+                       NS_GET_IID(nsIObserverService),
+                       observerService,
+                       PROXY_ASYNC,
+                       getter_AddRefs(obsProxy));
+  if (!obsProxy) return;
+
   if (aEntryName) {
     nsCOMPtr<nsISupportsCString> entry
       (do_CreateInstance (NS_SUPPORTS_CSTRING_CONTRACTID));
@@ -541,13 +550,11 @@ nsCategoryManager::NotifyObservers( const char *aTopic,
     if (NS_FAILED(rv))
       return;
 
-    observerService->NotifyObservers
-                       (entry, aTopic,
-                        NS_ConvertUTF8toUTF16(aCategoryName).get());
+    obsProxy->NotifyObservers(entry, aTopic,
+                              NS_ConvertUTF8toUTF16(aCategoryName).get());
   } else {
-    observerService->NotifyObservers
-                       (this, aTopic,
-                        NS_ConvertUTF8toUTF16(aCategoryName).get());
+    obsProxy->NotifyObservers(this, aTopic,
+                              NS_ConvertUTF8toUTF16(aCategoryName).get());
   }
 }
 

xpcom/components/nsCategoryManager.h

@@ -149,7 +149,8 @@ public:
    */
   NS_METHOD SuppressNotifications(PRBool aSuppress);
 
-  nsCategoryManager() { }
+  nsCategoryManager()
+    : mSuppressNotifications(PR_FALSE) { }
 private:
   friend class nsCategoryManagerFactory;
   static nsCategoryManager* Create();