Bug #387561 --> thunderbird equivalent of bug 386665. Fix a leak in the phishing detector.

r=phil

mail/base/content/messageWindow.js

@@ -549,7 +549,7 @@ function OnUnloadMessageWindow()
 {
 	// FIX ME - later we will be able to use onunload from the overlay
 	OnUnloadMsgHeaderPane();
-
+  gPhishingDetector.shutdown();
 	OnMailWindowUnload();
 }
 

mail/base/content/msgMail3PaneWindow.js

@@ -934,6 +934,9 @@ function OnUnloadMessenger()
   pref.removeObserver("mail.pane_config.dynamic", MailPrefObserver);
   pref.removeObserver("mail.showFolderPaneColumns", MailPrefObserver);
   document.getElementById('tabmail').closeTabs();
+
+  gPhishingDetector.shutdown();
+
   // FIX ME - later we will be able to use onload from the overlay
   OnUnloadMsgHeaderPane();
 

mail/components/phishing/phishing-warden.js

@@ -100,6 +100,7 @@ PROT_PhishingWarden.prototype.QueryInterface = function(iid) {
  * Cleanup on shutdown.
  */
 PROT_PhishingWarden.prototype.shutdown = function() {
+  this.prefs_.removeAllObservers();
 }
 
 /**