[MD settings] side nav routing to page sections

chrome/browser/resources/settings/settings_page/main_page_behavior.js

Index: chrome/browser/resources/settings/settings_page/main_page_behavior.js
diff --git a/chrome/browser/resources/settings/settings_page/main_page_behavior.js b/chrome/browser/resources/settings/settings_page/main_page_behavior.js
index 99dbc67c6181c689a6c3d63067f450ed323534c5..f4ce0b32dbfa6c45cde7eb2e34e34c78c0c64701 100644
--- a/chrome/browser/resources/settings/settings_page/main_page_behavior.js
+++ b/chrome/browser/resources/settings/settings_page/main_page_behavior.js
@@ -309,12 +309,14 @@ var MainPageBehaviorImpl = {
   },
 };
 
+
 /** @polymerBehavior */
 var MainPageBehavior = [
   TransitionBehavior,
   MainPageBehaviorImpl
 ];
 
+
 /**
  * TODO(michaelpg): integrate slide animations.
  * @polymerBehavior RoutableBehavior
@@ -329,13 +331,24 @@ var RoutableBehaviorImpl = {
     },
   },
 
+  /**
+   * @param {string} section Name of the item to scroll into view.
+   */
+  scrollToSection: function(section) {
+    if (section) {
+      // TODO(dschuyler): Determine whether this setTimeout can be removed.

[michaelpg, 2016/04/29 20:19:04]

I filed Polymer/polymer#3629 so you can link to that here.

[dschuyler, 2016/04/29 21:27:45]

Done.

+      setTimeout(function() {
+        var element = this.getSection_(section);
+        if (element)

[michaelpg, 2016/04/29 20:19:04]

Looks like this should be an assert.

[dschuyler, 2016/04/29 21:27:45]

Done. I removed the 'if' and made this one line.

+          element.scrollIntoView();
+      }.bind(this));
+    }
+  },
+
   /** @private */
   currentRouteChanged_: function(newRoute, oldRoute) {
-    // route.section is only non-empty when the user is within a subpage.
-    // When the user is not in a subpage, but on the Basic page, route.section
-    // is an empty string.
-    var newRouteIsSubpage = newRoute && newRoute.section;
-    var oldRouteIsSubpage = oldRoute && oldRoute.section;
+    var newRouteIsSubpage = newRoute && newRoute.subpage.length;
+    var oldRouteIsSubpage = oldRoute && oldRoute.subpage.length;
 
     if (!oldRoute && newRouteIsSubpage) {
       // Allow the page to load before expanding the section. TODO(michaelpg):
@@ -357,6 +370,8 @@ var RoutableBehaviorImpl = {
       var section = this.getSection_(newRoute.section);
       if (section)
         this.expandSection(section);
+    } else if (newRoute && newRoute.section) {
+      this.scrollToSection(newRoute.section);
     }
   },
 
@@ -372,6 +387,7 @@ var RoutableBehaviorImpl = {
   },
 };
 
+
 /** @polymerBehavior */
 var RoutableBehavior = [
   MainPageBehavior,