Add ChromeVox panel and implement caption display functionality.

chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js

Index: chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js
diff --git a/chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js b/chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js
index 1a68453e3f4eda41d6891077bf96069dd5c2b48c..c402278f4060beaa0715ca41b5fa301eea627c92 100644
--- a/chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js
+++ b/chrome/browser/resources/chromeos/chromevox/cvox2/background/background.js
@@ -375,8 +375,7 @@ Background.prototype = {
         }
         break;
       case 'showOptionsPage':
-        var optionsPage = {url: 'chromevox/background/options.html'};
-        chrome.tabs.create(optionsPage);
+        this.showOptionsPage();
         break;
       case 'toggleChromeVoxVersion':
         var newMode;
@@ -434,6 +433,14 @@ Background.prototype = {
   },
 
   /**
+   * Open the options page in a new tab.
+   */
+  showOptionsPage: function() {
+    var optionsPage = {url: 'chromevox/background/options.html'};
+    chrome.tabs.create(optionsPage);

[Peter Lundblad, 2015/11/06 15:00:58]

Just since you touch this, is chrome.runtime.openOptionsPage an alternative?
Perhaps just a TODO in this cl.

[dmazzoni, 2015/11/06 21:01:00]

Thanks. Works great, but only if you call it from the background page.

+  },
+
+  /**
    * Handles a braille command.
    * @param {!cvox.BrailleKeyEvent} evt
    * @param {!cvox.NavBraille} content