Bug 1136055 - 'Save link as' does not follow HTTP 302 response / redirection. r=gijs

--HG--
extra : rebase_source : e9add66a53f8f2627ed08d15e8462653563edd85

browser/base/content/nsContextMenu.js

@@ -1287,12 +1287,18 @@ nsContextMenu.prototype = {
       }
     }
 
-    // set up a channel to do the saving
+    // setting up a new channel for 'right click - save link as ...'
+    // ideally we should use:
+    // * doc            - as the loadingNode, and/or
+    // * this.principal - as the loadingPrincipal
+    // for now lets use systemPrincipal to bypass mixedContentBlocker
+    // checks after redirects, see bug: 1136055
     var ioService = Cc["@mozilla.org/network/io-service;1"].
                     getService(Ci.nsIIOService);
+    var principal = Services.scriptSecurityManager.getSystemPrincipal();
     var channel = ioService.newChannelFromURI2(makeURI(linkURL),
                                                null, // aLoadingNode
-                                               this.principal, // aLoadingPrincipal
+                                               principal, // aLoadingPrincipal
                                                null, // aTriggeringPrincipal
                                                Ci.nsILoadInfo.SEC_NORMAL,
                                                Ci.nsIContentPolicy.TYPE_OTHER);