Support Compat mode inside of the desktop tree.

chrome/browser/resources/chromeos/chromevox/host/chrome/host.js

Index: chrome/browser/resources/chromeos/chromevox/host/chrome/host.js
diff --git a/chrome/browser/resources/chromeos/chromevox/host/chrome/host.js b/chrome/browser/resources/chromeos/chromevox/host/chrome/host.js
index 19cdfb7fd71e9cbe2b8a0f92f31f10b235fe8834..3ceac54a502ea7db0ba79d68909abb85b33948fb 100644
--- a/chrome/browser/resources/chromeos/chromevox/host/chrome/host.js
+++ b/chrome/browser/resources/chromeos/chromevox/host/chrome/host.js
@@ -122,6 +122,9 @@ cvox.ChromeHost.prototype.init = function() {
     }});
 
   cvox.ExtensionBridge.addMessageListener(function(msg, port) {
+    if (!cvox.ChromeVox.documentHasFocus()) {

[dmazzoni, 2015/06/17 19:29:58]

Are there messages you do want to listen to here, like activate / inactivate?

[David Tseng, 2015/06/17 21:15:13]

toggling ChromeVox is now special cased; it turns out that on Chrome OS that
commnad is disallowed. Any others come to mind?

[dmazzoni, 2015/06/18 16:45:50]

This source file runs on other platforms, though. You don't want to break
ChromeVox Classic on Mac with this change.

[David Tseng, 2015/06/18 17:32:13]

If there's another sender of this message, then yes, this would break. I think
braille commands originating from the background page uses a different message
('brailleEvt').

With the latest patchset, I'm no longer sending ChromeVox commands from the
background page.

+      return;
+    }
     var message = msg['message'];
     if (message == 'USER_COMMAND') {
       var cmd = msg['command'];