[MD Bookmarks] Flatten sidebar.

chrome/browser/resources/md_bookmarks/folder_node.js

Index: chrome/browser/resources/md_bookmarks/folder_node.js
diff --git a/chrome/browser/resources/md_bookmarks/folder_node.js b/chrome/browser/resources/md_bookmarks/folder_node.js
index cb1ea0b46cfd9703b60f3ca75eb92236ad649fce..9de7634f01f860727530b378be0a2f2a79f70ede 100644
--- a/chrome/browser/resources/md_bookmarks/folder_node.js
+++ b/chrome/browser/resources/md_bookmarks/folder_node.js
@@ -15,6 +15,11 @@ Polymer({
       observer: 'updateFromStore',
     },
 
+    depth: {
+      type: Number,
+      observer: 'depthChanged_',
+    },
+
     /** @type {BookmarkNode} */
     item: Object,
 
@@ -34,9 +39,6 @@ Polymer({
     this.observe('item', function(state) {
       return state.nodes[this.itemId];
     }.bind(this));
-    this.observe('isClosed', function(state) {
-      return !!state.closedFolders[this.itemId];
-    }.bind(this));
     this.observe('selectedFolder', function(state) {
       return state.selectedFolder;
     });
@@ -74,6 +76,12 @@ Polymer({
         bookmarks.actions.changeFolderOpen(this.item.id, this.isClosed));
   },
 
+  /**
+   * @private
+   * @param {string} itemId
+   * @param {string} selectedFolder
+   * @return {boolean}
+   */
   computeIsSelected_: function(itemId, selectedFolder) {
     return itemId == selectedFolder;
   },
@@ -91,12 +99,9 @@ Polymer({
     return false;
   },
 
-  /**
-   * @param {string} itemId
-   * @private
-   * @return {boolean}
-   */
-  isFolder_: function(itemId) {
-    return !this.getState().nodes[itemId].url;
-  }
+  /** @private */
+  depthChanged_: function() {
+    this.$['folder-label'].style.paddingLeft =
+        `calc(${this.depth} * var(--padding-left-per-depth))`;
+  },
 });