Mark plugin requires restart code/resources Linux-only.

chrome/app/google_chrome_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This file contains definitions of strings that are specific to
 Google Chrome. These strings will be translated for each locale that Google
 Chrome supports. If you update this file, be sure also to update
 chromium_strings.grd. -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       output_all_resource_defines="false" source_lang_id="en" enc_check="möl">
   <outputs>
     <output filename="grit/google_chrome_strings.h" type="rc_header">
@@ skipping 1175 matching lines @@
       <message name="IDS_FEEDBACK_SERVICE_DIALOG_EXPLANATION_SCOUT" desc="Explanation of the dialog asking whether the user wants to upload some system information and page content for Safe Browsing analysis">
         You can help make Chrome safer and easier to use by automatically sending some system information and page content to Google to help detect dangerous apps and sites.
       </message>
 
       <!-- Desktop Capture -->
       <message name="IDS_DESKTOP_MEDIA_PICKER_SOURCE_TYPE_TAB" desc="Text for the button on the window picker dialog, clicking which takes one to tab sharing">
         Chrome Tab
       </message>
 
       <!-- Plugin Placeholders -->
-      <message name="IDS_PLUGIN_RESTART_REQUIRED" desc="The placeholder text for a plugin that can't be loaded until the browser is restarted.">
-        Restart Chrome to enable <ph name="PLUGIN_NAME">$1<ex>Flash</ex></ph>
-      </message>
+      <if expr="is_linux">
+        <message name="IDS_PLUGIN_RESTART_REQUIRED" desc="The placeholder text for a plugin that can't be loaded until the browser is restarted.">
+          Restart Chrome to enable <ph name="PLUGIN_NAME">$1<ex>Flash</ex></ph>
+        </message>
+      </if>
 
       <!-- Desktop to iOS promotion -->
       <message name="IDS_PASSWORD_MANAGER_DESKTOP_TO_IOS_PROMO_TEXT" desc="Text for Chrome iOS Promotion appearing in the password bubble after a password is saved.">
         Install Chrome on your phone. We’ll send an SMS to your phone.
       </message>
       <message name="IDS_PASSWORD_MANAGER_DESKTOP_TO_IOS_PROMO_TEXT_WITH_PHONE_NUMBER" desc="Text for Chrome iOS Promotion appearing in the password bubble after a password is saved.">
         Install Chrome on your phone. We’ll send an SMS to your phone: <ph name="PHONE_NUMBER">$1<ex>(650) 123-4567</ex></ph>
       </message>
       <message name="IDS_PASSWORD_MANAGER_DESKTOP_TO_IOS_PROMO_TEXT_V2" desc="Text for Chrome iOS Promotion appearing in the password bubble after a password is saved, this one mentioning explicitly that the SMS will be sent to the recovery phone number.">
         Install Chrome on your phone. We’ll send an SMS to your account recovery phone number.
@@ skipping 76 matching lines @@
         <message name="IDS_WIN10_WELCOME_PIN_SUBHEADING" desc="A subheading on a section which gives instructions on how to pin Chrome to the Windows 10 taskbar.">
           Pin Chrome to your taskbar
         </message>
         <message name="IDS_WIN10_WELCOME_SELECT" desc="An instruction asking the user to select Chrome from an external list of apps.">
           Select <ph name="SMALL_PRODUCT_LOGO">&lt;div class="logo-small"&gt;&lt;/div&gt;</ph> <ph name="BEGIN_BOLD">&lt;strong&gt;</ph>Google Chrome<ph name="END_BOLD">&lt;/strong&gt;</ph>
         </message>
       </if>
     </messages>
   </release>
 </grit>