Add mojo web UI framework based on Nat's TVCM

mojo/spy/ui/spy.html

+<!--
+Copyright 2014 The Chromium Authors. All rights reserved.
+Use of this source code is governed by a BSD-style license that can be
+found in the LICENSE file.
+-->
+<style>
+  x-spy-log-message {
+    display: block;
+    border-style: 1px solid black;
+    margin-top: 4px;
+    margin-bottom: 4px;
+  }
+
+  x-spy {
+    display: -webkit-flex;
+    -webkit-flex-direction: column;
+  }
+  x-spy > messages {
+    display: block;
+    -webkit-flex: 1 1 auto;
+  }
+  x-spy > form {
+    -webkit-flex: 0 0 auto;
+  }
+  x-spy > form > input {
+    width: 300px;
+  }
+</style>
+
+
+<template id="x-spy-template">
+  <messages>
+  </messages>
+  <input type="text" id="command" placeholder="enter spy command + enter" />
+</template>
+