Revert of MediaPerceptionPrivate API impl and testing.

extensions/test/data/media_perception_private/diagnostics/runtest.js

-// Copyright 2017 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.
-
-chrome.test.runTests([
-    function setStateRunning() {
-      // Need to start the mocked media analytics process.
-      chrome.mediaPerceptionPrivate.setState({
-        status: 'RUNNING'
-      }, chrome.test.callbackPass(function(state) {
-        chrome.test.assertEq({ status: 'RUNNING' }, state);
-      }));
-    },
-    function getDiagnostics() {
-      chrome.mediaPerceptionPrivate.getDiagnostics(
-          chrome.test.callbackPass(function(response) {
-            chrome.test.assertEq({
-              perceptionSamples: [{
-                framePerception: {
-                  frameId: 1
-                }
-              }]
-            }, response);
-          }));
-    }
-]);