[CrOS Settings] Add link to Chrome OS settings from browser settings.

Since we split settings between browser vs. OS, the settings page which
alerts the user about whether an OS update is available is part of OS
settings. However, some existing users were used to visiting
chrome://settings/help to check for this information. To ensure that
these users are not confused, this CL adds a link from the "About Chrome"
settings page to the "About Chrome OS" settings page.

Bug: 1010996
Change-Id: Ia7efc888195f444668d7b89617a698d03d4b9466
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1847906Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#704332}

chrome/app/settings_chromium_strings.grdp

@@ -26,6 +26,9 @@
     <message name="IDS_SETTINGS_ABOUT_OS" desc="Menu title for the About Chromium OS page.">
       About Chromium OS
     </message>
+    <message name="IDS_SETTINGS_ABOUT_SEE_OS_SETTINGS_FOR_UPDATE_MESSAGE" desc="Message shown to users on Chromium browser settings which alerts the user that OS updates are shown in Chromium OS settings.">
+      To see if your device is up to date, go to <ph name="LINK_BEGIN">&lt;a href="chrome://os-settings/help"&gt;</ph>Chromium OS Settings<ph name="LINK_END">&lt;/a&gt;</ph>
+    </message>
     <message name="IDS_SETTINGS_GET_HELP_USING_CHROME_OS" desc="Text of the button which takes the user to the Chrome help page.">
       Get help with Chromium OS
     </message>

chrome/app/settings_google_chrome_strings.grdp

@@ -26,6 +26,9 @@
     <message name="IDS_SETTINGS_ABOUT_OS" desc="Menu title for the About Chrome OS page.">
       About Chrome OS
     </message>
+    <message name="IDS_SETTINGS_ABOUT_SEE_OS_SETTINGS_FOR_UPDATE_MESSAGE" desc="Message shown to users on Chrome browser settings which alerts the user that OS updates are shown in Chrome OS settings.">
+      To see if your device is up to date, go to <ph name="LINK_BEGIN">&lt;a href="chrome://os-settings/help"&gt;</ph>Chrome OS Settings<ph name="LINK_END">&lt;/a&gt;</ph>
+    </message>
     <message name="IDS_SETTINGS_GET_HELP_USING_CHROME_OS" desc="Text of the button which takes the user to the Chrome help page.">
       Get help with Chrome OS
     </message>

chrome/browser/resources/settings/about_page/about_page.html

@@ -151,14 +151,19 @@
               </span>
 </if>
 <if expr="chromeos">
-             <div id="endOfLifeMessageContainer" hidden="[[!hasEndOfLife_]]">
-               $i18n{endOfLifeMessage}
-               <a href="$i18n{endOfLifeLearnMoreURL}" target="_blank">
-                 $i18n{learnMore}
-               </a>
-             </div>
+              <div id="endOfLifeMessageContainer" hidden="[[!hasEndOfLife_]]">
+                $i18n{endOfLifeMessage}
+                <a href="$i18n{endOfLifeLearnMoreURL}" target="_blank">
+                  $i18n{learnMore}
+                </a>
+              </div>
 </if>
               <div class="secondary">$i18n{aboutBrowserVersion}</div>
+<if expr="chromeos">
+              <div class="secondary"
+                  inner-h-t-m-l="[[getUpdateOsSettingsLink_()]]">
+              </div>
+</if>
             </div>
             <div class="separator" hidden="[[!showButtonContainer_]]"></div>
             <span id="buttonContainer" hidden="[[!showButtonContainer_]]">

chrome/browser/resources/settings/about_page/about_page.js

@@ -632,6 +632,20 @@ Polymer({
         this.i18nAdvanced('aboutProductOsLicense');
   },
 
+  // <if expr="chromeos">
+  /**
+   * @return {string}
+   * @private
+   */
+  getUpdateOsSettingsLink_: function() {
+    // Note: This string contains raw HTML and thus requires i18nAdvanced().
+    // Since the i18n template syntax (e.g., $i18n{}) does not include an
+    // "advanced" version, it's not possible to inline this link directly in the
+    // HTML.
+    return this.i18nAdvanced('aboutUpdateOsSettingsLink');
+  },
+  // </if>
+
   /**
    * @param {boolean} enabled True if Crostini is enabled.
    * @private

chrome/browser/ui/webui/settings/settings_localized_strings_provider.cc

@@ -447,6 +447,8 @@ void AddAboutStrings(content::WebUIDataSource* html_source) {
      IDS_SETTINGS_ABOUT_PAGE_RELAUNCH_AND_POWERWASH},
     {"aboutRollbackInProgress", IDS_SETTINGS_UPGRADE_ROLLBACK_IN_PROGRESS},
     {"aboutRollbackSuccess", IDS_SETTINGS_UPGRADE_ROLLBACK_SUCCESS},
+    {"aboutUpdateOsSettingsLink",
+     IDS_SETTINGS_ABOUT_SEE_OS_SETTINGS_FOR_UPDATE_MESSAGE},
     {"aboutUpgradeUpdatingChannelSwitch",
      IDS_SETTINGS_UPGRADE_UPDATING_CHANNEL_SWITCH},
     {"aboutUpgradeSuccessChannelSwitch",