Add views::View::set_preferred_size, use it in a few places.

ash/BUILD.gn

 # Copyright 2014 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/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/base/ui_features.gni")
 
 # Historical note: Ash shipped on Windows for a couple years to support
@@ skipping 486 matching lines @@
     "system/tiles/tray_tiles.cc",
     "system/tiles/tray_tiles.h",
     "system/toast/toast_data.cc",
     "system/toast/toast_data.h",
     "system/toast/toast_manager.cc",
     "system/toast/toast_manager.h",
     "system/toast/toast_overlay.cc",
     "system/toast/toast_overlay.h",
     "system/tray/actionable_view.cc",
     "system/tray/actionable_view.h",
-    "system/tray/fixed_sized_image_view.cc",
-    "system/tray/fixed_sized_image_view.h",
     "system/tray/hover_highlight_view.cc",
     "system/tray/hover_highlight_view.h",
     "system/tray/ime_info.cc",
     "system/tray/ime_info.h",
     "system/tray/label_tray_view.cc",
     "system/tray/label_tray_view.h",
     "system/tray/size_range_layout.cc",
     "system/tray/size_range_layout.h",
     "system/tray/system_menu_button.cc",
     "system/tray/system_menu_button.h",
@@ skipping 993 matching lines @@
     "//content/public/app:both",
     "//device/bluetooth",
   ]
 
   data_deps = [
     "//ash/strings:ash_test_strings",
     "//ash/resources:ash_test_resources_with_content_100_percent",
     "//ash/resources:ash_test_resources_200_percent",
   ]
 }