Remove old cc-frame-viewer now that it is upstreamed into trace_viewer

tools/cc-frame-viewer/app/viewer.css

-/* Copyright (c) 2012 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.
- */
-html {
-  height: 100%;
-  width: 100%;
-  overflow: hidden;
-}
-
-body {
-  overflow: hidden;
-  margin: 0;
-  padding: 0;
-  height: 100%;
-  width: 100%;
-  font-family: Arial, Helvetica, sans-serif, Tahoma, Verdana, sans-serif;
-  font-size: 10pt;
-  background: #ededed;
-}
-
-body {
-  display: -webkit-flex;
-  -webkit-flex-direction: column;
-}
-
-#viewer {
-  -webkit-flex: 1;
-  display: -webkit-flex;
-}
-
-#viewer > x-model-view {
-  -webkit-flex: 1;
-}