Add setting to isolate zoom changes by default.

chrome/browser/resources/options/browser_options.js

 // Copyright (c) 2012 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.
 
 cr.exportPath('options');
 
 /**
  * @typedef {{actionLinkText: (string|undefined),
  *            accountInfo: (string|undefined),
  *            childUser: (boolean|undefined),
@@ skipping 664 matching lines @@
         var value = event.target.options[event.target.selectedIndex].value;
         Preferences.setIntegerPref(
              'webkit.webprefs.default_fixed_font_size',
              value - OptionsPage.SIZE_DIFFERENCE_FIXED_STANDARD, true);
         chrome.send('defaultFontSizeAction', [String(value)]);
       };
       $('defaultZoomFactor').onchange = function(event) {
         chrome.send('defaultZoomFactorAction',
             [String(event.target.options[event.target.selectedIndex].value)]);
       };
+      $('defaultZoomScope').onchange = function(event) {
+        chrome.send('defaultZoomScopeAction',
+            [event.target.checked]);
+      };
       $('safeBrowsingExtendedReportingCheckbox').onchange = function(event) {
         chrome.send('safeBrowsingExtendedReportingAction',
             [event.target.checked]);
       };
 
       // Languages section.
       var showLanguageOptions = function(event) {
         PageManager.showPageByName('languages');
         chrome.send('coreOptionsUserMetricsAction',
             ['Options_LanuageAndSpellCheckSettings']);
@@ skipping 1318 matching lines @@
       var value, title, selected;
       for (var i = 0; i < items.length; i++) {
         title = items[i][0];
         value = items[i][1];
         selected = items[i][2];
         element.appendChild(new Option(title, value, false, selected));
       }
     },
 
     /**
+     * Set the checked state of the default zoom scope checkbox.
+     * @param {boolean} checked Whether to check the checkbox.
+     * @private
+     */
+    setupZoomScopeCheckbox_: function(checked) {
+      $('defaultZoomScope').checked = checked;
+    },
+
+    /**
      * Shows/hides the autoOpenFileTypesResetToDefault button and label, with
      * animation.
      * @param {boolean} display Whether to show the button and label or not.
      * @private
      */
     setAutoOpenFileTypesDisplayed_: function(display) {
       if ($('advanced-settings').hidden) {
         // If the Advanced section is hidden, don't animate the transition.
         $('auto-open-file-types-section').hidden = !display;
       } else {
@@ skipping 379 matching lines @@
     'setNowSectionVisible',
     'setProfilesInfo',
     'setSpokenFeedbackCheckboxState',
     'setSystemTimezoneAutomaticDetectionManaged',
     'setSystemTimezoneManaged',
     'setThemesResetButtonEnabled',
     'setVirtualKeyboardCheckboxState',
     'setWallpaperManaged',
     'setupPageZoomSelector',
     'setupProxySettingsButton',
+    'setupZoomScopeCheckbox',
     'showCreateProfileError',
     'showCreateProfileSuccess',
     'showCreateProfileWarning',
     'showHotwordAlwaysOnSection',
     'showHotwordNoDspSection',
     'showHotwordSection',
     'showMouseControls',
     'showSupervisedUserImportError',
     'showSupervisedUserImportSuccess',
     'showTouchpadControls',
@@ skipping 39 matching lines @@
 
       settings.hidden = !isVisible;
     };
   }
 
   // Export
   return {
     BrowserOptions: BrowserOptions
   };
 });