MD History: Synced Tabs fixes

chrome/browser/resources/md_history/synced_device_manager.js

Index: chrome/browser/resources/md_history/synced_device_manager.js
diff --git a/chrome/browser/resources/md_history/synced_device_manager.js b/chrome/browser/resources/md_history/synced_device_manager.js
index 12e67fddbe540238b32f22538bf1542ee2947b2d..2a73361fdef0d90c39705c9da4586965852e6da6 100644
--- a/chrome/browser/resources/md_history/synced_device_manager.js
+++ b/chrome/browser/resources/md_history/synced_device_manager.js
@@ -5,6 +5,7 @@
 /**
  * @typedef {{device: string,
  *           lastUpdateTime: string,
+ *           opened: boolean,
  *           separatorIndexes: !Array<number>,
  *           timestamp: number,
  *           tabs: !Array<!ForeignSessionTab>,
@@ -59,6 +60,7 @@ Polymer({
 
   listeners: {
     'toggle-menu': 'onToggleMenu_',
+    'scroll': 'onListScroll_'
   },
 
   /** @override */
@@ -105,6 +107,7 @@ Polymer({
     return {
       device: session.name,
       lastUpdateTime: '– ' + session.modifiedTime,
+      opened: true,
       separatorIndexes: separatorIndexes,
       timestamp: session.timestamp,
       tabs: tabs,
@@ -116,6 +119,12 @@ Polymer({
     chrome.send('startSignInFlow');
   },
 
+  onListScroll_: function() {
+    var menu = this.$.menu.getIfExists();
+    if (menu)
+      menu.closeMenu();
+  },
+
   onToggleMenu_: function(e) {
     this.$.menu.get().then(function(menu) {
       menu.toggleMenu(e.detail.target, e.detail.tag);
@@ -209,9 +218,16 @@ Polymer({
       }
     }
 
-    // Then, append any new devices.
-    for (var i = updateCount; i < sessionList.length; i++) {
-      this.push('syncedDevices_', this.createInternalDevice_(sessionList[i]));
+    if (sessionList.length >= this.syncedDevices_.length) {
+      // The list grew; append new items.
+      for (var i = updateCount; i < sessionList.length; i++) {
+        this.push('syncedDevices_', this.createInternalDevice_(sessionList[i]));
+      }
+    } else {
+      // The list shrank; remove deleted items.
+      this.splice(
+          'syncedDevices_', updateCount,
+          this.syncedDevices_.length - updateCount);
     }
   },