Minor cleanup.

common/content/commandline.js

@@ -260,9 +260,10 @@ var CommandWidgets = Class("CommandWidgets", {
             configurable: true, enumerable: true,
             get: function get_whenReady() {
                 let elem = document.getElementById(id);
-                while (elem.contentDocument.documentURI != elem.getAttribute("src") ||
-                       ["viewable", "complete"].indexOf(elem.contentDocument.readyState) < 0)
-                    util.threadYield();
+
+                util.waitFor(function () elem.contentDocument.documentURI === elem.getAttribute("src") &&
+                       ["viewable", "complete"].indexOf(elem.contentDocument.readyState) >= 0);
+
                 res = res || (processor || util.identity).call(self, elem);
                 return res;
             }
@@ -1189,9 +1190,8 @@ var CommandLine = Module("commandline", {
                     this.waiting = true;
                     for (let [, context] in Iterator(list)) {
                         let done = function done() !(idx >= n + context.items.length || idx == -2 && !context.items.length);
-                        while (context.incomplete && !done())
-                            util.threadYield(false, true);
 
+                        util.waitFor(function () !context.incomplete || done())
                         if (done())
                             break;
 
@@ -1420,7 +1420,7 @@ var CommandLine = Module("commandline", {
                  let command = commandline.command;
 
                  self.accepted = true;
-                 return function () modes.pop();
+                 return function () { modes.pop(); };
              });
 
         [

common/content/dactyl.js

@@ -1191,8 +1191,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
 
                 case dactyl.NEW_WINDOW:
                     let win = window.openDialog(document.documentURI, "_blank", "chrome,all,dialog=no");
-                    while (win.document.readyState != "complete")
-                        util.threadYield();
+                    util.waitFor(function () win.document.readyState === "complete");
                     browser = win.getBrowser();
                     // FALLTHROUGH
                 case dactyl.CURRENT_TAB:

common/content/events.js

@@ -526,7 +526,7 @@ var Events = Module("events", {
             if (quiet)
                 commandline.quiet = quiet;
 
-            util.threadYield(1, true);
+            util.threadYield(1, true); // Why? --Kris
 
             for (let [, evt_obj] in Iterator(events.fromString(keys))) {
                 let now = Date.now();
@@ -922,8 +922,6 @@ var Events = Module("events", {
      * @returns {boolean}
      */
     waitForPageLoad: function (time) {
-        util.threadYield(true); // clear queue
-
         if (buffer.loaded)
             return true;
 
@@ -1267,7 +1265,7 @@ var Events = Module("events", {
 
             let urlbar = document.getElementById("urlbar");
             if (elem == null && urlbar && urlbar.inputField == this._lastFocus)
-                util.threadYield(true);
+                util.threadYield(true); // Why? --Kris
 
             while (modes.main.ownsFocus)
                  modes.pop(null, { fromFocus: true });

common/content/tabs.js

@@ -203,12 +203,14 @@ var Tabs = Module("tabs", {
     getGroups: function () {
         if ("_groups" in this)
             return this._groups;
+
         if (window.TabView && TabView._initFrame)
             TabView._initFrame();
+
         let iframe = document.getElementById("tab-view");
-        this._groups = this._groups = iframe ? iframe.contentWindow : null;
-        while (this._groups && !this._groups.TabItems)
-            util.threadYield(false, true);
+        this._groups = iframe ? iframe.contentWindow : null;
+        if (this._groups)
+            util.waitFor(function () this._groups.TabItems, this);
         return this._groups;
     },