Rename sync string for Themes on non-ChromeOS

Bug: 896515
Change-Id: Idd45447bd092e934286f0b574782b92caa61a051
Reviewed-on: https://chromium-review.googlesource.com/c/1301517Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Thomas Tangl <tangltom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603458}

chrome/app/settings_strings.grdp

@@ -3627,9 +3627,16 @@
   <message name="IDS_SETTINGS_HISTORY_CHECKBOX_LABEL" desc="Label for the checkbox which enables or disables syncing history between multiple browser instances.">
     History
   </message>
+<if expr="chromeos">
   <message name="IDS_SETTINGS_THEMES_AND_WALLPAPERS_CHECKBOX_LABEL" desc="Label for the checkbox which enables or disables syncing themes and wallpapers between multiple browser instances.">
     Themes &amp; Wallpapers
   </message>
+</if>
+<if expr="not chromeos">
+  <message name="IDS_SETTINGS_THEMES_AND_WALLPAPERS_CHECKBOX_LABEL" desc="Label for the checkbox which enables or disables syncing themes and wallpapers between multiple browser instances.">
+    Themes
+  </message>
+</if>
   <message name="IDS_SETTINGS_BOOKMARKS_CHECKBOX_LABEL" desc="Label for the checkbox which enables or disables syncing bookmarks between multiple browser instances.">
     Bookmarks
   </message>