Revert "Get unread messages from the server in the web app."

This reverts commit c953759486.

The client side logic for dealing with server counts is actually
fine, as far as we know, but there are still some data-related
issues with cleaning up old unread counts.

frontend_tests/node_tests/unread.js

@@ -18,6 +18,9 @@ var stream_data = require('js/stream_data.js');
 set_global('stream_data', stream_data);
 set_global('blueslip', {});
 set_global('page_params', {});
+set_global('feature_flags', {
+    load_server_counts: true,
+});
 
 var Dict = global.Dict;
 var muting = global.muting;

static/js/feature_flags.js

@@ -2,6 +2,8 @@ var feature_flags = (function () {
 
 var exports = {};
 
+exports.load_server_counts = false;
+
 // Experimental modification to support much wider message views.
 exports.full_width = false;
 

static/js/unread.js

@@ -480,7 +480,9 @@ exports.load_server_counts = function () {
 };
 
 exports.initialize = function () {
-    exports.load_server_counts();
+    if (feature_flags.load_server_counts) {
+        exports.load_server_counts();
+    }
 };
 
 return exports;