Add a StateManager for managing hotwording state based on various factors

chrome/browser/resources/hotword/manager.js

 // 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.
 
 'use strict';

[Dan Beam, 2014/08/27 20:08:36]

we generally scope 'use strict' just in case files are combined together

 
 /**
  * @fileoverview This extension provides hotword triggering capabilites to
  * Chrome.
  *
  * This extension contains all the JavaScript for loading and managing the
  * hotword detector. The hotword detector and language model data will be
  * provided by a shared module loaded from the web store.
  */
 
+// Hotwording state.
+var stateManager = new hotword.StateManager();
+
+// Detect Chrome startup and make sure we get a chance to run.
+chrome.runtime.onStartup.addListener(function() {
+  stateManager.updateStatus();
+}.bind(this));

[Dan Beam, 2014/08/26 18:40:51]

remove .bind(this)

[Anand Mistry (off Chromium), 2014/08/27 07:10:55]

Done.

+
+// Detect when hotword settings have changed.
+chrome.hotwordPrivate.onEnabledChanged.addListener(function() {
+  stateManager.updateStatus();
+}.bind(this));

[Dan Beam, 2014/08/26 18:40:51]

remove .bind(this)

[Anand Mistry (off Chromium), 2014/08/27 07:10:55]

Done.

+
+// Detect when the shared module containing the NaCL module and language model
+// is installed.
+chrome.management.onInstalled.addListener(function(info) {
+  if (info.id == hotword.constants.SHARED_MODULE_ID) {

[Dan Beam, 2014/08/26 18:40:51]

nit: no curlies

[Anand Mistry (off Chromium), 2014/08/27 07:10:55]

Looking into this, the style guide gives no preference either way. The Chrome
code base also doesn't consistently enforce this, and I've seen cases where both
styles exist in a single file. Is this preference documented somewhere? If not,
I'd like to continue using braces for single line blocks. There's already one
existing file in this extension with that style... and it's the one I prefer.

[Dan Beam, 2014/08/27 20:08:36]

chrome is quite consistent on this rule.
where?  point me at the code and i'll be happy to fix this for you :).
"""Do not use braces for single-line logic blocks."""
http://www.chromium.org/developers/web-development-style-guide

additionally, http://www.chromium.org/developers/coding-style discourages use of
extra { } for conditional 1-liners.

one could also interpret "Do not needlessly surround the return expression with
parentheses" [1] as another in opposition of superfluous characters.

[1]
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Return...

[Anand Mistry (off Chromium), 2014/08/28 00:59:25]

Thanks. Both those pages point to the google style guides as reference, which is
what I was following. I guess I should have read those pages carefully instead
of skimming them.

+    chrome.runtime.reload();
+  }
+});
+
+// Detect when a session has requested to be started and stopped.
+chrome.hotwordPrivate.onHotwordSessionRequested.addListener(function() {
+  // TODO(amistry): This event should change state depending on whether the user
+  // has enabled always-on hotwording. But for now, always signal the start of a
+  // hotwording session. This allows this extension to work with the app
+  // launcher in the current state.
+  chrome.hotwordPrivate.setHotwordSessionState(true, function() {});
+});
+
+chrome.hotwordPrivate.onHotwordSessionStopped.addListener(function() {
+  chrome.hotwordPrivate.setHotwordSessionState(false, function() {});
+});
+