bluetooth: Add device details page with basic properties to internals page.

ui/webui/resources/js/cr/ui/page_manager/page_manager.js

Index: ui/webui/resources/js/cr/ui/page_manager/page_manager.js
diff --git a/ui/webui/resources/js/cr/ui/page_manager/page_manager.js b/ui/webui/resources/js/cr/ui/page_manager/page_manager.js
index 99599b1ed2ce8d87eca1c0d30744159b25fe4e79..40907226ec0af3c2389b5263e0d0b52dbed9150d 100644
--- a/ui/webui/resources/js/cr/ui/page_manager/page_manager.js
+++ b/ui/webui/resources/js/cr/ui/page_manager/page_manager.js
@@ -83,6 +83,14 @@ cr.define('cr.ui.pageManager', function() {
     },
 
     /**
+     * Unregisters an existing page.
+     * @param {!cr.ui.pageManager.Page} page Page to unregister.
+     */
+    unregister: function(page) {
+      delete this.registeredPages[page.name.toLowerCase()];

[dpapad, 2017/01/12 22:53:21]

Is it necessary to unregister a page? I am wondering if unregistering a page can
cause an obsolete entry to remain in history. See lines 201-202.

[mbrunson, 2017/01/12 23:09:19]

Unregistering a page can create an obsolete entry but I think it's up to
observers to update and handle the history appropriately. PageManager doesn't
set window.history or window.location directly. Because of this, I created a
PageObserver that updates the history stack by changing location.hash after
receiving the new path from PageManager[1]. An event handler determines if this
change is valid and shows the page[2]. If it's invalid, the page is not updated.

[1] (Line 49)
https://codereview.chromium.org/2576603002/diff/240001/chrome/browser/resourc...
[2] (Line 256)
https://codereview.chromium.org/2576603002/diff/240001/chrome/browser/resourc...

+    },
+
+    /**
      * Registers a new Overlay page.
      * @param {!cr.ui.pageManager.Page} overlay Overlay to register.
      * @param {cr.ui.pageManager.Page} parentPage Associated parent page for