Refactor guest view availability to be API not permission based.

chrome/common/extensions/api/_api_features.json

 // 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.
 
 // This features file defines extension APIs implemented under src/chrome.
 // See extensions/common/features/* to understand this file, in particular
 // feature.h, simple_feature.h, and base_feature_provider.h.
 //
 // Note that specifying "web_page", "blessed_web_page", or "all" as a context
 // type will require manually updating chrome/renderer/resources/dispatcher.cc.
@@ skipping 38 matching lines @@
     "contexts": [
       "blessed_extension",
       "unblessed_extension",
       "content_script",
       "web_page",
       "blessed_web_page"
     ],
     // Any webpage can use the app API.
     "matches": ["<all_urls>"]
   },
+  // The API for the *embedder* of appview. Appview has both an embedder and
+  // guest API, which are different.
+  "appViewEmbedderInternal": {
+    "internal": true,
+    "contexts": ["blessed_extension"],
+    "dependencies": ["permission:appview"]
+  },
+  // TODO(fsamuel,kalman): Rename this appViewGuestInternal.
   "appViewInternal": {
     "internal": true,
     "channel": "dev",
     "contexts": ["blessed_extension"]
   },
   "app.window": {
     "channel": "stable",
     "contexts": ["blessed_extension"],
     "extension_types": ["platform_app"],
     "noparent": true
@@ skipping 741 matching lines @@
     "internal": true,
     "channel": "stable",
     "dependencies": ["permission:webview"],
     "contexts": ["blessed_extension"]
   },
   "windows": {
     "dependencies": ["api:tabs"],
     "contexts": ["blessed_extension"]
   }
 }