[ios] TextBadgeView interface, implementation, and unit test stubs

ios/chrome/browser/ui/tools_menu/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 source_set("tools_menu") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "reading_list_menu_view_item.h",
     "reading_list_menu_view_item.mm",
+    "text_badge_view.h",

[edchin, 2017/06/27 00:39:42]

Per our discussion, please move this to the reading list folder. 

+    "text_badge_view.mm",
     "tools_menu_constants.h",
     "tools_menu_constants.mm",
     "tools_menu_model.h",
     "tools_menu_model.mm",
     "tools_menu_view_controller.h",
     "tools_menu_view_controller.mm",
     "tools_menu_view_item.h",
     "tools_menu_view_item.mm",
     "tools_menu_view_tools_cell.h",
     "tools_menu_view_tools_cell.mm",
@@ skipping 63 matching lines @@
     "//ios/chrome/browser/ui:ui_internal",
     "//ios/chrome/browser/ui/toolbar",
     "//ios/chrome/test/earl_grey:test_support",
     "//ios/third_party/earl_grey",
     "//ios/web/public/test",
     "//ios/web/public/test/http_server",
     "//ui/base",
   ]
   libs = [ "XCTest.framework" ]
 }