--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -217,18 +217,16 @@ XPCOMUtils.defineLazyGetter(this, "Win7F
       onCloseWindow() {
         AeroPeek.onCloseWindow(window);
       }
     };
   }
   return null;
 });
 
-const nsIWebNavigation = Ci.nsIWebNavigation;
-
 var gBrowser;
 var gLastValidURLStr = "";
 var gInPrintPreviewMode = false;
 var gContextMenu = null; // nsContextMenu instance
 var gMultiProcessBrowser =
   window.QueryInterface(Ci.nsIInterfaceRequestor)
         .getInterface(Ci.nsIWebNavigation)
         .QueryInterface(Ci.nsILoadContext)
@@ -1190,17 +1188,17 @@ var gBrowserInit = {
   delayedStartupFinished: false,
 
   onDOMContentLoaded() {
     gBrowser = window._gBrowser;
     delete window._gBrowser;
     gBrowser.init();
 
     window.QueryInterface(Ci.nsIInterfaceRequestor)
-          .getInterface(nsIWebNavigation)
+          .getInterface(Ci.nsIWebNavigation)
           .QueryInterface(Ci.nsIDocShellTreeItem).treeOwner
           .QueryInterface(Ci.nsIInterfaceRequestor)
           .getInterface(Ci.nsIXULWindow)
           .XULBrowserWindow = window.XULBrowserWindow;
     window.QueryInterface(Ci.nsIDOMChromeWindow).browserDOMWindow =
       new nsBrowserAccess();
 
     let initBrowser = gBrowser.initialBrowser;
@@ -2169,19 +2167,18 @@ function BrowserHandleShiftBackspace() {
     break;
   case 1:
     goDoCommand("cmd_scrollPageDown");
     break;
   }
 }
 
 function BrowserStop() {
-  const stopFlags = nsIWebNavigation.STOP_ALL;
   maybeRecordAbandonmentTelemetry(gBrowser.selectedTab, "stop");
-  gBrowser.webNavigation.stop(stopFlags);
+  gBrowser.webNavigation.stop(Ci.nsIWebNavigation.STOP_ALL);
 }
 
 function BrowserReloadOrDuplicate(aEvent) {
   let metaKeyPressed = AppConstants.platform == "macosx"
                        ? aEvent.metaKey
                        : aEvent.ctrlKey;
   var backgroundTabModifier = aEvent.button == 1 || metaKeyPressed;
 
@@ -2197,23 +2194,24 @@ function BrowserReloadOrDuplicate(aEvent
     duplicateTabIn(gBrowser.selectedTab, where);
 }
 
 function BrowserReload() {
   if (gBrowser.currentURI.schemeIs("view-source")) {
     // Bug 1167797: For view source, we always skip the cache
     return BrowserReloadSkipCache();
   }
-  const reloadFlags = nsIWebNavigation.LOAD_FLAGS_NONE;
+  const reloadFlags = Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
   BrowserReloadWithFlags(reloadFlags);
 }
 
 function BrowserReloadSkipCache() {
   // Bypass proxy and cache.
-  const reloadFlags = nsIWebNavigation.LOAD_FLAGS_BYPASS_PROXY | nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE;
+  const reloadFlags = Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_PROXY |
+                      Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE;
   BrowserReloadWithFlags(reloadFlags);
 }
 
 var BrowserHome = BrowserGoHome;
 function BrowserGoHome(aEvent) {
   if (aEvent && "button" in aEvent &&
       aEvent.button == 2) // right-click: do nothing
     return;
@@ -3148,17 +3146,17 @@ var BrowserOnClick = {
     }
   },
 
   ignoreWarningLink(reason, blockedInfo) {
     // Allow users to override and continue through to the site,
     // but add a notify bar as a reminder, so that they don't lose
     // track after, e.g., tab switching.
     gBrowser.loadURIWithFlags(gBrowser.currentURI.spec,
-                              nsIWebNavigation.LOAD_FLAGS_BYPASS_CLASSIFIER,
+                              Ci.nsIWebNavigation.LOAD_FLAGS_BYPASS_CLASSIFIER,
                               null, null, null);
 
     Services.perms.add(gBrowser.currentURI, "safe-browsing",
                        Ci.nsIPermissionManager.ALLOW_ACTION,
                        Ci.nsIPermissionManager.EXPIRE_SESSION);
 
     let buttons = [{
       label: gNavigatorBundle.getString("safebrowsing.getMeOutOfHereButton.label"),
@@ -5316,21 +5314,21 @@ nsBrowserAccess.prototype = {
         break;
       default : // OPEN_CURRENTWINDOW or an illegal value
         newWindow = window.content;
         if (aURI) {
           let loadflags = isExternal ?
                             Ci.nsIWebNavigation.LOAD_FLAGS_FROM_EXTERNAL :
                             Ci.nsIWebNavigation.LOAD_FLAGS_NONE;
           gBrowser.loadURIWithFlags(aURI.spec, {
-                                    aTriggeringPrincipal,
-                                    flags: loadflags,
-                                    referrerURI: referrer,
-                                    referrerPolicy,
-                                    });
+            aTriggeringPrincipal,
+            flags: loadflags,
+            referrerURI: referrer,
+            referrerPolicy,
+          });
         }
         if (!Services.prefs.getBoolPref("browser.tabs.loadDivertedInBackground"))
           window.focus();
     }
     return newWindow;
   },
 
   createContentWindowInFrame: function browser_createContentWindowInFrame(
@@ -6200,17 +6198,17 @@ function BrowserSetForcedCharacterSet(aC
     // Save the forced character-set
     if (!PrivateBrowsingUtils.isWindowPrivate(window))
       PlacesUtils.setCharsetForURI(getWebNavigation().currentURI, aCharset);
   }
   BrowserCharsetReload();
 }
 
 function BrowserCharsetReload() {
-  BrowserReloadWithFlags(nsIWebNavigation.LOAD_FLAGS_CHARSET_CHANGE);
+  BrowserReloadWithFlags(Ci.nsIWebNavigation.LOAD_FLAGS_CHARSET_CHANGE);
 }
 
 function UpdateCurrentCharset(target) {
   let selectedCharset = CharsetMenu.foldCharset(gBrowser.selectedBrowser.characterSet);
   for (let menuItem of target.getElementsByTagName("menuitem")) {
     let isSelected = menuItem.getAttribute("charset") === selectedCharset;
     menuItem.setAttribute("checked", isSelected);
   }

--- a/browser/base/content/web-panels.js
+++ b/browser/base/content/web-panels.js
@@ -56,43 +56,43 @@ var panelProgressListener = {
     }
 };
 
 var gLoadFired = false;
 function loadWebPanel(aURI) {
     var panelBrowser = getPanelBrowser();
     if (gLoadFired) {
         panelBrowser.webNavigation
-                    .loadURI(aURI, nsIWebNavigation.LOAD_FLAGS_NONE,
+                    .loadURI(aURI, Ci.nsIWebNavigation.LOAD_FLAGS_NONE,
                              null, null, null);
     }
     panelBrowser.setAttribute("cachedurl", aURI);
 }
 
 function load() {
     var panelBrowser = getPanelBrowser();
     panelBrowser.webProgress.addProgressListener(panelProgressListener,
                                                  Ci.nsIWebProgress.NOTIFY_ALL);
     panelBrowser.messageManager.loadFrameScript("chrome://browser/content/content.js", true);
     var cachedurl = panelBrowser.getAttribute("cachedurl");
     if (cachedurl) {
         panelBrowser.webNavigation
-                    .loadURI(cachedurl, nsIWebNavigation.LOAD_FLAGS_NONE, null,
+                    .loadURI(cachedurl, Ci.nsIWebNavigation.LOAD_FLAGS_NONE, null,
                              null, null);
     }
 
     gLoadFired = true;
 }
 
 function unload() {
     getPanelBrowser().webProgress.removeProgressListener(panelProgressListener);
 }
 
 function PanelBrowserStop() {
-    getPanelBrowser().webNavigation.stop(nsIWebNavigation.STOP_ALL);
+    getPanelBrowser().webNavigation.stop(Ci.nsIWebNavigation.STOP_ALL);
 }
 
 function PanelBrowserReload() {
     getPanelBrowser().webNavigation
                      .sessionHistory
-                     .QueryInterface(nsIWebNavigation)
-                     .reload(nsIWebNavigation.LOAD_FLAGS_NONE);
+                     .QueryInterface(Ci.nsIWebNavigation)
+                     .reload(Ci.nsIWebNavigation.LOAD_FLAGS_NONE);
 }