Merge fx-team to m-c a=merge

browser/components/customizableui/test/browser_880164_customization_context_menus.js

@@ -116,7 +116,7 @@ add_task(function() {
   let urlBarContainer = document.getElementById("urlbar-container");
   // Need to make sure not to click within an edit field.
   let urlbarRect = urlBarContainer.getBoundingClientRect();
-  EventUtils.synthesizeMouse(urlBarContainer, 100, urlbarRect.height - 1, {type: "contextmenu", button: 2 });
+  EventUtils.synthesizeMouse(urlBarContainer, 100, 1, {type: "contextmenu", button: 2 });
   yield shownPromise;
 
   let expectedEntries = [

toolkit/devtools/server/actors/webbrowser.js

@@ -285,7 +285,7 @@ BrowserTabList.prototype._getBrowsers = function*() {
 };
 
 BrowserTabList.prototype._getChildren = function(aWindow) {
-  return aWindow.gBrowser.browsers;
+  return aWindow.gBrowser ? aWindow.gBrowser.browsers : [];
 };
 
 BrowserTabList.prototype._isRemoteBrowser = function(browser) {