Remove some more !IsModeMaterial code.

chrome/app/theme/theme_resources.grd

 <?xml version="1.0" encoding="utf-8"?>
 <!-- This grd file contains images that are pre-scaled for device scale
      factors. The image returned by |base::ResourceBundle::GetImageNamed|
      will contain multiple |gfx:ImageSkiaReps| for each scale factors. The
      |fallback_to_low_resolution| attribute controls behavior when
      an image file is missing for target scale factor. If true, chrome
      will automatically scale the 1x image to the target scale factor.
      If false, build will fail due to missing resources. This is
      currently set to true for all resources, but the default will
      become false in near future.
@@ skipping 52 matching lines @@
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MAXIMIZE" file="common/app_window_maximize.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MAXIMIZE_D" file="common/app_window_maximize_disabled.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MAXIMIZE_H" file="common/app_window_maximize_hover.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MAXIMIZE_L" file="common/app_window_maximize_light.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MAXIMIZE_P" file="common/app_window_maximize_active.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MINIMIZE" file="common/app_window_minimize.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MINIMIZE_H" file="common/app_window_minimize_hover.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MINIMIZE_L" file="common/app_window_minimize_light.png" />
         <structure type="chrome_scaled_image" name="IDR_APP_WINDOW_MINIMIZE_P" file="common/app_window_minimize_active.png" />
       </if>
-      <if expr="use_ash">
-        <structure type="chrome_scaled_image" name="IDR_ASH_BROWSER_WINDOW_HEADER_SHADE_LEFT" file="common/ash/browser_window_header_shade_left.png" />
-        <structure type="chrome_scaled_image" name="IDR_ASH_BROWSER_WINDOW_HEADER_SHADE_RIGHT" file="common/ash/browser_window_header_shade_right.png" />
-        <structure type="chrome_scaled_image" name="IDR_ASH_BROWSER_WINDOW_HEADER_SHADE_TOP" file="common/ash/browser_window_header_shade_top.png" />
-        <structure type="chrome_scaled_image" name="IDR_ASH_BROWSER_WINDOW_HEADER_SHADE_TOP_LEFT" file="common/ash/browser_window_header_shade_top_left.png" />
-        <structure type="chrome_scaled_image" name="IDR_ASH_BROWSER_WINDOW_HEADER_SHADE_TOP_RIGHT" file="common/ash/browser_window_header_shade_top_right.png" />
-      </if>
       <structure type="chrome_scaled_image" name="IDR_AUTOFILL_DIALOG_MENU_BUTTON" file="common/autofill_dialog_menu_button_normal.png" />
       <structure type="chrome_scaled_image" name="IDR_AUTOFILL_DIALOG_MENU_BUTTON_P" file="common/autofill_dialog_menu_button_pressed.png" />
       <structure type="chrome_scaled_image" name="IDR_AUTOFILL_DIALOG_MENU_BUTTON_H" file="common/autofill_dialog_menu_button_hover.png" />
       <structure type="chrome_scaled_image" name="IDR_AUTOFILL_DIALOG_MENU_BUTTON_D" file="common/autofill_dialog_menu_button_disabled.png" />
       <if expr="toolkit_views or is_macosx or is_ios">
         <structure type="chrome_scaled_image" name="IDR_BACK" file="common/browser_back_normal.png" />
         <structure type="chrome_scaled_image" name="IDR_BACK_D" file="common/browser_back_disabled.png" />
         <structure type="chrome_scaled_image" name="IDR_BACK_H" file="common/browser_back_hover.png" />
         <structure type="chrome_scaled_image" name="IDR_BACK_P" file="common/browser_back_pressed.png" />
       </if>
@@ skipping 552 matching lines @@
         <structure type="chrome_scaled_image" name="IDR_THEME_TAB_BACKGROUND_INCOGNITO" file="common/ash/theme_default_inactive.png" />
       </if>
       <if expr="is_macosx or is_ios">
         <structure type="chrome_scaled_image" name="IDR_THEME_TAB_BACKGROUND" file="mac/theme_default_inactive.png" />
         <structure type="chrome_scaled_image" name="IDR_THEME_TAB_BACKGROUND_INACTIVE" file="mac/theme_default_inactive_background.png" />
         <if expr="mac_views_browser">
           <structure type="chrome_scaled_image" name="IDR_THEME_TAB_BACKGROUND_INCOGNITO" file="mac/theme_default_inactive.png" />
         </if>
       </if>
       <structure type="chrome_scaled_image" name="IDR_THEME_TAB_BACKGROUND_V" file="theme_tab_background_glass.png" />
-      <if expr="not use_ash and not is_macosx and not is_ios">
-        <structure type="chrome_scaled_image" name="IDR_THEME_TOOLBAR" file="theme_toolbar_default.png" />
-      </if>
-      <if expr="use_ash">
-        <!-- Ash has a dark gray toolbar background, Windows has light gray. -->
-        <structure type="chrome_scaled_image" name="IDR_THEME_TOOLBAR" file="common/ash/theme_default_active.png" />
+      <if expr="not is_macosx and not is_ios">
+        <structure type="chrome_scaled_image" name="IDR_THEME_TOOLBAR" file="notused.png" />

[Peter Kasting, 2016/10/21 21:07:50]

Nit: Might be good to have a comment noting that we still need this identifier
so themes can provide a custom image for it?  (Although I suppose if Mac/iOS
dropped the image, we could drop it from here, and just define it as some
theme-specific identifier in some other enum...)

[Evan Stade, 2016/10/21 22:11:11]

Done.

       </if>
       <if expr="is_macosx or is_ios">
         <structure type="chrome_scaled_image" name="IDR_THEME_TOOLBAR" file="mac/theme_default_active.png" />
         <structure type="chrome_scaled_image" name="IDR_THEME_TOOLBAR_INACTIVE" file="mac/theme_default_active_background.png" />
       </if>
       <!-- Instant Extended API toolbar background is common for all platforms. -->
       <structure type="chrome_scaled_image" name="IDR_THEME_WINDOW_CONTROL_BACKGROUND" file="notused.png" />
       <if expr="is_macosx">
         <structure type="chrome_scaled_image" name="IDR_THROBBER_WAITING" file="legacy/throbber_waiting.png" />
         <structure type="chrome_scaled_image" name="IDR_THROBBER_WAITING_INCOGNITO" file="mac/throbber_waiting_incognito.png" />
         <structure type="chrome_scaled_image" name="IDR_THROBBER_INCOGNITO" file="mac/throbber_incognito.png" />
       </if>
-      <if expr="use_ash">
-        <structure type="chrome_scaled_image" name="IDR_TOOLBAR_SHADE_LEFT" file="common/toolbar_shade_left.png" />
-        <structure type="chrome_scaled_image" name="IDR_TOOLBAR_SHADE_RIGHT" file="common/toolbar_shade_right.png" />
-        <structure type="chrome_scaled_image" name="IDR_TOOLBAR_SHADE_TOP" file="common/toolbar_shade_top.png" />
-      </if>
       <if expr="is_macosx or is_ios">
         <structure type="chrome_scaled_image" name="IDR_TOOLBAR_SHADE_TOP" file="mac/toolbar_shade_top.png" />
       </if>
 
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_BOTTOM_LEFT" file="common/toolbar_action_highlight_bottom_left.png" />
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_BOTTOM" file="common/toolbar_action_highlight_bottom.png" />
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_BOTTOM_RIGHT" file="common/toolbar_action_highlight_bottom_right.png" />
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_CENTER" file="common/toolbar_action_highlight_center.png" />
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_LEFT" file="common/toolbar_action_highlight_left.png" />
       <structure type="chrome_scaled_image" name="IDR_TOOLBAR_ACTION_HIGHLIGHT_RIGHT" file="common/toolbar_action_highlight_right.png" />
@@ skipping 29 matching lines @@
         <structure type="chrome_scaled_image" name="IDR_WEBSTORE_ICON_32" file="google_chrome/webstore_icon_32.png" />
       </if>
       <if expr="is_macosx">
         <structure type="chrome_scaled_image" name="IDR_ZOOM_MINUS" file="legacy/zoom_minus.png" />
         <structure type="chrome_scaled_image" name="IDR_ZOOM_PLUS" file="legacy/zoom_plus.png" />
         <structure type="chrome_scaled_image" name="IDR_ZOOM_NORMAL" file="legacy/zoom_reset.png" />
       </if>
     </structures>
   </release>
 </grit>