Bug 1476218 - Part 1 - Update Tracking Protection section in the identity popup for Content Blocking. r=nhnt11

This commit switches the identity popup to use "Content Blocking" as a top-level section
instead of Tracking Protection, which is now demoted to a category of Content Blocking.

To keep this change halfway reviewable, I avoided renaming variables, classNames, ids, etc.
that use the term trackingProtection if they were otherwise unaffected by this patch. There
will be other patches that can do this in the future

Differential Revision: https://phabricator.services.mozilla.com/D2775

browser/base/content/global-scripts.inc

@@ -15,6 +15,7 @@ for (let script of [
 
   "chrome://browser/content/browser-captivePortal.js",
   "chrome://browser/content/browser-compacttheme.js",
+  "chrome://browser/content/browser-contentblocking.js",
   "chrome://browser/content/browser-feeds.js",
   "chrome://browser/content/browser-media.js",
   "chrome://browser/content/browser-pageActions.js",
@@ -23,7 +24,6 @@ for (let script of [
   "chrome://browser/content/browser-sidebar.js",
   "chrome://browser/content/browser-siteIdentity.js",
   "chrome://browser/content/browser-tabsintitlebar.js",
-  "chrome://browser/content/browser-trackingprotection.js",
 
   "chrome://global/content/globalOverlay.js",
   "chrome://browser/content/utilityOverlay.js",