Bug 67857 - Profile Mgr resets all prefs which is SLOW.

modules/libpref/public/nsIPref.idl

@@ -67,6 +67,7 @@ interface nsIPref : nsISupports {
   void StartUp();
   void ReadUserPrefs();
   void ReadUserPrefsFrom(in nsIFileSpec spec);
+  void ResetUserPrefs();
   void ResetPrefs();
   void ShutDown();
 

modules/libpref/src/nsPref.cpp

@@ -615,6 +615,14 @@ NS_IMETHODIMP nsPref::ReadUserPrefsFrom(nsIFileSpec* inFile)
     return rv;
 } // nsPref::ReadUserPrefsFrom
 
+//----------------------------------------------------------------------------------------
+NS_IMETHODIMP nsPref::ResetUserPrefs()
+//----------------------------------------------------------------------------------------
+{
+    PREF_ClearAllUserPrefs();
+    return NS_OK;    
+}
+
 //----------------------------------------------------------------------------------------
 NS_IMETHODIMP nsPref::ResetPrefs()
 //----------------------------------------------------------------------------------------

profile/src/nsProfile.cpp

@@ -1586,8 +1586,8 @@ nsresult nsProfile::LoadNewProfilePrefs()
     nsresult rv;
     NS_WITH_SERVICE(nsIPref, prefs, kPrefCID, &rv);
     if (NS_FAILED(rv)) return rv;
-
-    prefs->ResetPrefs();
+    
+    prefs->ResetUserPrefs();
     prefs->ReadUserPrefs();
 
     return NS_OK;