Fix some initialization order issues.

common/content/commandline.js

@@ -1390,7 +1390,7 @@ var CommandLine = Module("commandline", {
                 subCommand: 0
             });
     },
-    modes: function () {
+    modes: function initModes() {
         modes.addMode("COMMAND_LINE", {
             char: "c",
             description: "Active when the command line is focused",

common/content/hints.js

@@ -1115,7 +1115,8 @@ var Hints = Module("hints", {
     Mode: Struct("HintMode", "name", "prompt", "action", "tags", "filter")
             .localize("prompt")
 }, {
-    modes: function () {
+    modes: function initModes() {
+        initModes.require("commandline");
         modes.addMode("HINTS", {
             extended: true,
             description: "Active when selecting elements in QuickHint or ExtendedHint mode",

common/content/modes.js

@@ -426,6 +426,10 @@ var Modes = Module("modes", {
 }, {
     Mode: Class("Mode", {
         init: function init(name, options, params) {
+            if (options.bases)
+                util.assert(options.bases.every(function (m) m instanceof this, this.constructor),
+                            "Invalid bases", true);
+
             update(this, {
                 id: 1 << Modes.Mode._id++,
                 name: name,