Settings: Move more privacy subpages/dialogs to lazy_load.html.

Specifically moving
 - clear_browsing_data_dialog/clear_browsing_data_dialog.html
 - privacy_page/cookies_page.html
 - privacy_page/security_page.html
 - site_settings/all_sites.html

Which results in 15.4% less JS/HTML code loaded during Settings
startup (measured on Linux builds)

vulcanized.html: 342K -> 286K  (-16.4%)
crisper.js: 390K -> 333K (-14.6%)

lazy_load.vulcanized.html: 153K -> 209K (+27%)
lazy_load.crisper.js: 189K -> 246K (+30%)

Also fixing a bug that was revealed as a result of these changes
where <settings-ui> was not properly clearing some global state
when it was detached from the DOM, causing test failures.

Bug: 1026064,1032584
Change-Id: Ibf6ef69916ae7a656b9b2576947294bea87ef5c5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2090840Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: dpapad <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#748417}

chrome/browser/resources/settings/global_scroll_target_behavior.js

@@ -18,7 +18,7 @@
 // #import {Route, Router, RouteObserverBehavior} from './router.m.js';
 
 cr.define('settings', function() {
-  const scrollTargetResolver = new PromiseResolver();
+  let scrollTargetResolver = new PromiseResolver();
 
   /** @polymerBehavior */
   const GlobalScrollTargetBehaviorImpl = {
@@ -98,9 +98,13 @@ cr.define('settings', function() {
    * This should only be called once.
    * @param {HTMLElement} scrollTarget
    */
-  const setGlobalScrollTarget = function(scrollTarget) {
+  function setGlobalScrollTarget(scrollTarget) {
     scrollTargetResolver.resolve(scrollTarget);
-  };
+  }
+
+  function resetGlobalScrollTargetForTesting() {
+    scrollTargetResolver = new PromiseResolver();
+  }
 
   // This is done to make the closure compiler happy: it needs fully qualified
   // names when specifying an array of behaviors.
@@ -113,7 +117,7 @@ cr.define('settings', function() {
     GlobalScrollTargetBehaviorImpl: GlobalScrollTargetBehaviorImpl,
     GlobalScrollTargetBehavior: GlobalScrollTargetBehavior,
     setGlobalScrollTarget: setGlobalScrollTarget,
+    resetGlobalScrollTargetForTesting: resetGlobalScrollTargetForTesting,
     scrollTargetResolver: scrollTargetResolver,
   };
 });
-

chrome/browser/resources/settings/lazy_load.html

@@ -7,8 +7,12 @@
   <link rel="import" href="autofill_page/password_check.html">
   <link rel="import" href="autofill_page/passwords_section.html">
   <link rel="import" href="autofill_page/payments_section.html">
+  <link rel="import" href="clear_browsing_data_dialog/clear_browsing_data_dialog.html">
   <link rel="import" href="search_engines_page/search_engines_page.html">
+  <link rel="import" href="privacy_page/cookies_page.html">
   <link rel="import" href="privacy_page/security_keys_subpage.html">
+  <link rel="import" href="privacy_page/security_page.html">
+  <link rel="import" href="site_settings/all_sites.html">
   <link rel="import" href="site_settings/site_data_details_subpage.html">
   <link rel="import" href="site_settings_page/site_settings_page.html">
   <link rel="import" href="site_settings/category_default_setting.html">

chrome/browser/resources/settings/privacy_page/privacy_page.html

@@ -10,12 +10,9 @@
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="do_not_track_toggle.html">
 <link rel="import" href="secure_dns.html">
-<link rel="import" href="security_page.html">
 <link rel="import" href="passwords_leak_detection_toggle.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-collapse/iron-collapse.html">
-<link rel="import" href="../clear_browsing_data_dialog/clear_browsing_data_dialog.html">
 <link rel="import" href="../controls/settings_toggle_button.html">
-<link rel="import" href="cookies_page.html">
 <link rel="import" href="../metrics_browser_proxy.html">
 <link rel="import" href="../people_page/sync_browser_proxy.html">
 <link rel="import" href="../prefs/prefs.html">
@@ -25,7 +22,6 @@
 <link rel="import" href="../settings_page/settings_animated_pages.html">
 <link rel="import" href="../settings_page/settings_subpage.html">
 <link rel="import" href="../settings_shared_css.html">
-<link rel="import" href="../site_settings/all_sites.html">
 <link rel="import" href="../site_settings/constants.html">
 
 <link rel="import" href="privacy_page_browser_proxy.html">

chrome/browser/resources/settings/settings_ui/settings_ui.js

@@ -177,6 +177,7 @@ cr.define('settings', function() {
     /** @override */
     detached() {
       settings.Router.getInstance().resetRouteForTesting();
+      settings.resetGlobalScrollTargetForTesting();
     },
 
     /** @param {!settings.Route} route */

chrome/test/data/webui/settings/all_sites_tests.js

@@ -59,7 +59,10 @@ suite('AllSites', function() {
   });
 
   // Initialize a site-list before each test.
-  setup(function() {
+  setup(async function() {
+    PolymerTest.clearBody();
+    await settings.forceLazyLoaded();
+
     prefsVarious = test_util.createSiteSettingsPrefs([], [
       test_util.createContentSettingTypeToValuePair(
           settings.ContentSettingsTypes.GEOLOCATION,
@@ -87,7 +90,6 @@ suite('AllSites', function() {
     localDataBrowserProxy = new TestLocalDataBrowserProxy();
     settings.SiteSettingsPrefsBrowserProxyImpl.instance_ = browserProxy;
     settings.LocalDataBrowserProxyImpl.instance_ = localDataBrowserProxy;
-    PolymerTest.clearBody();
     testElement = document.createElement('all-sites');
     assertTrue(!!testElement);
     document.body.appendChild(testElement);

chrome/test/data/webui/settings/privacy_page_test.js

@@ -143,12 +143,14 @@ cr.define('settings_privacy_page', function() {
         });
       });
 
-      setup(function() {
+      setup(async function() {
+        PolymerTest.clearBody();
+        await settings.forceLazyLoaded();
+
         const testBrowserProxy = new TestPrivacyPageBrowserProxy();
         settings.PrivacyPageBrowserProxyImpl.instance_ = testBrowserProxy;
         const testSyncBrowserProxy = new TestSyncBrowserProxy();
         settings.SyncBrowserProxyImpl.instance_ = testSyncBrowserProxy;
-        PolymerTest.clearBody();
 
         page = document.createElement('settings-privacy-page');
         page.prefs = {