Add a method to enable ChromeVox Next easily for the current run.

This cl adds a key sequence that enables ChromeVox Next. Eventually, this can turn into a proper option.

TEST=open ChromeVox options page, type 'n', 'e', 'x', 't'. Observe message and ChromeVox Next is enabled on all newly opened tabs.

Review URL: https://codereview.chromium.org/1107343006

Cr-Commit-Position: refs/heads/master@{#327541}

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

@@ -98,6 +98,31 @@ cvox.OptionsPage.init = function() {
     $('version').textContent =
         chrome.app.getDetails().version;
   }
+
+  // Temporary secret way to enable ChromeVox Next for the current run of
+  // ChromeVox.
+  var next = 'next';
+  document.body.addEventListener('keypress', function(evt) {
+    if (next === undefined) {
+      return;
+    }
+    var key = String.fromCharCode(evt.charCode);
+    if (next[0] === key) {
+      next = next.slice(1);
+
+      if (next === '') {
+        cvox.OptionsPage.speak(
+            'You are now running ChromeVox Next; open a new tab to start',
+            cvox.QueueMode.FLUSH);
+        next = undefined;
+        chrome.extension.getBackgroundPage()['global']
+            .backgroundObj.forceChromeVoxNextActive();
+      }
+    } else {
+      next = 'next';
+    }
+    return true;
+  }, true);
 };
 
 /**

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

@@ -77,6 +77,11 @@ Background = function() {
 };
 
 Background.prototype = {
+  /** Forces ChromeVox Next to be active for all tabs. */
+  forceChromeVoxNextActive: function() {
+    this.active_ = true;
+  },
+
   /**
    * Handles all setup once a new automation tree appears.
    * @param {chrome.automation.AutomationNode} desktop
@@ -248,7 +253,7 @@ Background.prototype = {
    * @param {Object} evt
    */
   onLoadComplete: function(evt) {
-    var next = this.isWhitelisted_(evt.target.attributes.url);
+    var next = this.isWhitelisted_(evt.target.attributes.url) || this.active_;
     this.toggleChromeVoxVersion({next: next, classic: !next});
     // Don't process nodes inside of web content if ChromeVox Next is inactive.
     if (evt.target.root.role != chrome.automation.RoleType.desktop &&