Show favicons when blocking third party images.

bug 256172, r=dwitte, sr=shaver

extensions/cookie/nsImgManager.cpp

@@ -280,6 +280,16 @@ nsImgManager::TestPermission(nsIURI *aCurrentURI,
     if (!aFirstURI)
       return NS_OK;
 
+    PRBool trustedSource = PR_FALSE;
+    rv = aFirstURI->SchemeIs("chrome", &trustedSource);
+    NS_ENSURE_SUCCESS(rv,rv);
+    if (!trustedSource) {
+      rv = aFirstURI->SchemeIs("resource", &trustedSource);
+      NS_ENSURE_SUCCESS(rv,rv);
+    }
+    if (trustedSource)
+      return NS_OK;
+
     // compare tails of names checking to see if they have a common domain
     // we do this by comparing the tails of both names where each tail 
     // includes at least one dot