Sync online wallpaper

chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js

Index: chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js
diff --git a/chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js b/chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js
index b069aa472cba0b266a53e357d22b9b39ba7bfa3f..0271fb0f9dd99e91ae9be085bbd1815570618fb8 100644
--- a/chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js
+++ b/chrome/browser/resources/chromeos/wallpaper_manager/js/event_page.js
@@ -36,8 +36,8 @@ SurpriseWallpaper.prototype.tryChangeWallpaper = function() {
   // Try to fetch newest rss as document from server first. If any error occurs,
   // proceed with local copy of rss.
   WallpaperUtil.fetchURL(Constants.WallpaperRssURL, 'document', function(xhr) {
-    WallpaperUtil.saveToLocalStorage(Constants.AccessRssKey,
-        new XMLSerializer().serializeToString(xhr.responseXML));
+    WallpaperUtil.saveToStorage(Constants.AccessRssKey,
+        new XMLSerializer().serializeToString(xhr.responseXML), false);
     self.updateSurpriseWallpaper(xhr.responseXML);
   }, onFailure);
 };
@@ -139,8 +139,10 @@ SurpriseWallpaper.prototype.setRandomWallpaper_ = function(dateString) {
       var wallpaper = manifest.wallpaper_list[index];
       var wallpaperURL = wallpaper.base_url + Constants.HighResolutionSuffix;
       var onSuccess = function() {
-        WallpaperUtil.saveToLocalStorage(
-            Constants.AccessLastSurpriseWallpaperChangedDate, dateString);
+        WallpaperUtil.saveToStorage(
+            Constants.AccessLastSurpriseWallpaperChangedDate,
+            dateString,
+            false);
       }
       WallpaperUtil.setOnlineWallpaper(wallpaperURL, wallpaper.default_layout,
           onSuccess, self.retryLater_.bind(self));
@@ -180,8 +182,8 @@ SurpriseWallpaper.prototype.setWallpaperFromRssItem_ = function(item,
 SurpriseWallpaper.prototype.disable = function() {
   chrome.alarms.clearAll();
   // Makes last changed date invalid.
-  WallpaperUtil.saveToLocalStorage(
-      Constants.AccessLastSurpriseWallpaperChangedDate, '');
+  WallpaperUtil.saveToStorage(Constants.AccessLastSurpriseWallpaperChangedDate,
+                              '', false);
 };
 
 /**
@@ -236,6 +238,18 @@ chrome.storage.onChanged.addListener(function(changes, namespace) {
     } else {
       SurpriseWallpaper.getInstance().disable();
     }
+  } else if (changes[Constants.AccessWallpaperInfoKey]) {

[flackr, 2013/04/26 03:51:16]

This shouldn't be else if, just if. Both keys may have changed.

[bshe, 2013/04/26 16:56:51]

Done.

+    var newValue = changes[Constants.AccessWallpaperInfoKey].newValue;
+    var oldValue = changes[Constants.AccessWallpaperInfoKey].oldValue;
+    // oldValue equals undefined indicate that sync just happened.
+    if (oldValue == undefined &&

[flackr, 2013/04/26 03:51:16]

Why only if oldValue is undefined? I think it would be nice to have a change on
one computer change the wallpapers on the other computers.

[bshe, 2013/04/26 16:56:51]

You are right. It doesn't handle the case you mention.

I wasn't able to find a easy way to detect if the value is changed because of
sync or user action. But after spend more time on it, it seems we can use an
extra local value to easily distinguish the two cases.

On 2013/04/26 03:51:16, flackr wrote:

+        newValue.source == Constants.WallpaperSourceEnum.Online) {
+      // TODO(bshe): Consider schedule an alarm to set online wallpaper later
+      // when failed. Note that we need to cancel the retry if user set another
+      // wallpaper before retry alarm invoked.
+      WallpaperUtil.setOnlineWallpaper(newValue.url, newValue.layout,
+          function() {}, function() {});
+    }
   }
 });