mash: Remove ShelfDelegate; move functions to ShelfModel.

ash/test/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.
 
 import("//build/config/ui.gni")
 
 static_library("test_support_without_content") {
   testonly = true
   sources = [
     "ash_test_environment_default.cc",
@@ skipping 104 matching lines @@
     "test_palette_delegate.cc",
     "test_palette_delegate.h",
     "test_screenshot_delegate.cc",
     "test_screenshot_delegate.h",
     "test_session_controller_client.cc",
     "test_session_controller_client.h",
     "test_session_state_animator.cc",
     "test_session_state_animator.h",
     "test_session_state_delegate.cc",
     "test_session_state_delegate.h",
-    "test_shelf_delegate.cc",
-    "test_shelf_delegate.h",
-    "test_shelf_item_delegate.cc",
-    "test_shelf_item_delegate.h",
     "test_shell_delegate.cc",
     "test_shell_delegate.h",
     "test_system_tray_delegate.cc",
     "test_system_tray_delegate.h",
     "test_system_tray_item.cc",
     "test_system_tray_item.h",
     "test_wallpaper_delegate.cc",
     "test_wallpaper_delegate.h",
     "tray_cast_test_api.cc",
     "tray_cast_test_api.h",
@@ skipping 70 matching lines @@
   deps = [
     ":test_support_with_content",
     "//base",
     "//skia",
     "//testing/gtest",
     "//ui/aura",
     "//ui/base",
     "//ui/gl:test_support",
   ]
 }