Bug 461199 (Part 12) - mozilla::dom::Link should unregister with mozilla::IHistory when it goes away

Call UnregisterWithHistory in Link's destructor to ensure that we are no longer
registered with IHistory.
r=sicking
sr=bz

content/base/src/Link.cpp

@@ -58,6 +58,11 @@ Link::Link()
 {
 }
 
+Link::~Link()
+{
+  UnregisterFromHistory();
+}
+
 nsLinkState
 Link::GetLinkState() const
 {
@@ -461,13 +466,11 @@ Link::UnregisterFromHistory()
     return;
   }
 
-  // Obtain the URI that we registered with.
-  nsCOMPtr<nsIURI> hrefURI(GetURI());
-  NS_ASSERTION(hrefURI, "mRegistered is true, but we have no URI?!");
+  NS_ASSERTION(mCachedURI, "mRegistered is true, but we have no cached URI?!");
 
   // And tell History to stop tracking us.
   IHistory *history = nsContentUtils::GetHistory();
-  nsresult rv = history->UnregisterVisitedCallback(hrefURI, this);
+  nsresult rv = history->UnregisterVisitedCallback(mCachedURI, this);
   NS_ASSERTION(NS_SUCCEEDED(rv), "This should only fail if we misuse the API!");
   if (NS_SUCCEEDED(rv)) {
     mRegistered = false;

content/base/src/Link.h

@@ -93,6 +93,8 @@ protected:
    */
   virtual void ResetLinkState();
 
+  virtual ~Link();
+
 private:
   /**
    * Unregisters from History so this node no longer gets notifications about

toolkit/components/places/tests/cpp/mock_Link.h

@@ -94,6 +94,10 @@ Link::Link()
 {
 }
 
+Link::~Link()
+{
+}
+
 nsLinkState
 Link::GetLinkState() const
 {