Implement easy GPU feature status summary.

chrome/browser/resources/gpu_internals/browser_bridge.js

 // Copyright (c) 2011 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.
-
 cr.define('gpu', function() {
   /**
-   * This class provides a 'bridge' for communicating between javascript and
-   * the browser.
+   * This class provides a 'bridge' for communicating between javascript and the
+   * browser. When run outside of WebUI, e.g. as a regular webpage, it provides
+   * synthetic data to assist in testing.
    * @constructor
    */
   function BrowserBridge() {
     // If we are not running inside WebUI, output chrome.send messages
     // to the console to help with quick-iteration debugging.
     if (chrome.send === undefined && console.log) {
       this.debugMode_ = true;
-      chrome.send = function(messageHandler, args) {
-        console.log('chrome.send', messageHandler, args);
-      };
+      var browserBridgeTests = document.createElement('script');
+      browserBridgeTests.src = './gpu_internals/browser_bridge_tests.js';
+      document.body.appendChild(browserBridgeTests);
     } else {
       this.debugMode_ = false;
     }
 
     this.nextRequestId_ = 0;
     this.pendingCallbacks_ = [];
+    this.logMessages_ = [];
 
     // Tell c++ code that we are ready to receive GPU Info.
-    chrome.send('browserBridgeInitialized');
+    if (!this.debugMode_) {
+      chrome.send('browserBridgeInitialized');
+      this.beginRequestClientInfo_();
+      this.beginRequestLogMessages_();
+    }
   }
 
   BrowserBridge.prototype = {
     __proto__: cr.EventTarget.prototype,
 
+    applySimulatedData_: function applySimulatedData(data) {
+      // set up things according to the simulated data
+      this.gpuInfo_ = data.gpuInfo;
+      this.clientInfo_ = data.clientInfo;
+      this.logMessages_ = data.logMessages;
+      cr.dispatchSimpleEvent(this, 'gpuInfoUpdate');
+      cr.dispatchSimpleEvent(this, 'clientInfoChange');
+      cr.dispatchSimpleEvent(this, 'logMessagesChange');
+    },
+
     /**
      * Returns true if the page is hosted inside Chrome WebUI
      * Helps have behavior conditional to emulate_webui.py
      */
     get debugMode() {
       return this.debugMode_;
     },
 
     /**
      * Sends a message to the browser with specified args. The
@@ skipping 29 matching lines @@
     get gpuInfo() {
       return this.gpuInfo_;
     },
 
     /**
      * Called from gpu c++ code when GPU Info is updated.
      */
     onGpuInfoUpdate: function(gpuInfo) {
       this.gpuInfo_ = gpuInfo;
       cr.dispatchSimpleEvent(this, 'gpuInfoUpdate');
+    },
+
+    /**
+     * This function begins a request for the ClientInfo. If it comes back
+     * as undefined, then we will issue the request again in 250ms.
+     */
+    beginRequestClientInfo_: function() {
+      this.callAsync('requestClientInfo', undefined, (function(data) {
+        if (data === undefined) { // try again in 250 ms
+          window.setTimeout(this.beginRequestClientInfo_.bind(this), 250);
+        } else {
+          this.clientInfo_ = data;
+          cr.dispatchSimpleEvent(this, 'clientInfoChange');
+        }
+      }).bind(this));
+    },
+
+    /**
+     * Returns information about the currently runnign Chrome build.
+     */
+    get clientInfo() {
+      return this.clientInfo_;
+    },
+
+    /**
+     * This function checks for new GPU_LOG messages.
+     * If any are found, a refresh is triggered.
+     */
+    beginRequestLogMessages_: function() {
+      this.callAsync('requestLogMessages', undefined,
+          (function(messages) {
+            if (messages.length != this.logMessages_.length) {
+              this.logMessages_ = messages;
+              cr.dispatchSimpleEvent(this, 'logMessagesChange');
+            }
+            // check again in 250 ms
+            window.setTimeout(this.beginRequestLogMessages_.bind(this), 250);
+          }).bind(this));
+    },
+
+    /**
+     * Returns an array of log messages issued by the GPU process, if any.
+     */
+    get logMessages() {
+      return this.logMessages_;
     }
+
   };
 
   return {
     BrowserBridge: BrowserBridge
   };
 });