Sync 3rd party wallpaper app name

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

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 var WallpaperUtil = {
   strings: null,  // Object that contains all the flags
   syncFs: null,   // syncFileSystem handler
   webkitFs: null  // webkitFileSystem handler
 };
 
@@ skipping 196 matching lines @@
 WallpaperUtil.storeWallpaperToLocalFS = function(wallpaperFilename,
     wallpaperData, saveDir) {
   if (!wallpaperData) {
     console.error('wallpaperData is null');
     return;
   }
   var getDirSuccess = function(dirEntry) {
     dirEntry.getFile(wallpaperFilename,
                     {create: false},
                     function() {},  // already exists
                     function(e) {   // not exists, create

[tbarzic, 2016/02/04 21:31:24]

Not really related to this cl, so feel to ignore for now:
Shouldn't this check for the error.

Also, I think this does exactly what you need (writes a new file, but only if it
doesn't already exist) 
dirEntry.getFile(wallpaperFileName,
                 {create: true, exclusive: true},
                 function(fileEntry) {
                    WallpaperUtil.writeFile(fileEntry, wallpaperData)
                 },
                 errorCallback);

btw, do all wallpapers have unique file path (since files are not overwritten)?

[xdai1, 2016/02/05 01:09:52]

Yes, every wallpaper has its unique file path. The custom wallpaper filename
uses the time (the number of milliseconds since midnight Jan 1 1970) when it was
set. The third party filename uses the prefix combined with the time when it was
set. I will address it in another CL.

                     dirEntry.getFile(wallpaperFilename, {create: true},
                                      function(fe) {
                                        WallpaperUtil.writeFile(fe,
                                                                wallpaperData);
                                      },
                                      WallpaperUtil.onFileSystemError);
                     });
   };
   WallpaperUtil.requestLocalFS(function(fs) {
     fs.root.getDirectory(saveDir, {create: true}, getDirSuccess,
                          WallpaperUtil.onFileSystemError);
   });
 };
 
 /**
  * Sets wallpaper from synced file system.
  * @param {string} wallpaperFilename File name used to set wallpaper.
  * @param {string} wallpaperLayout Layout used to set wallpaper.
+ * @param {string} appName If non-empty, the current wallpaper is set by a third

[tbarzic, 2016/02/04 21:31:24]

wdyt about changing method signature to (possibly in a follow-up)

/**
 * @param {{fileName: string, layout: string | undefined, appName: string}}
 * @param {function=} onSuccess
 */
function(options, onSuccess) {
}

I'm fine if you'd prefer not to.

+ *     party wallpaper. Otherwise, it is set by the built-in wallpaper picker.
  * @param {function=} onSuccess Callback if set successfully.
  */
 WallpaperUtil.setCustomWallpaperFromSyncFS = function(
-    wallpaperFilename, wallpaperLayout, onSuccess) {
+    wallpaperFilename, wallpaperLayout, appName, onSuccess) {
   var setWallpaperFromSyncCallback = function(fs) {
     if (!wallpaperFilename) {
       console.error('wallpaperFilename is not provided.');
       return;
     }
     if (!wallpaperLayout)
       wallpaperLayout = 'CENTER_CROPPED';
     fs.root.getFile(wallpaperFilename, {create: false}, function(fileEntry) {
       fileEntry.file(function(file) {
         var reader = new FileReader();
         reader.onloadend = function() {
           chrome.wallpaperPrivate.setCustomWallpaper(
               reader.result,
               wallpaperLayout,
               true,
               wallpaperFilename,
               function(thumbnailData) {
                 // TODO(ranj): Ignore 'canceledWallpaper' error.
                 if (chrome.runtime.lastError) {
                   console.error(chrome.runtime.lastError.message);
                   return;
                 }
-                WallpaperUtil.storeWallpaperToLocalFS(wallpaperFilename,
-                    reader.result, Constants.WallpaperDirNameEnum.ORIGINAL);
-                WallpaperUtil.storeWallpaperToLocalFS(wallpaperFilename,
-                    thumbnailData, Constants.WallpaperDirNameEnum.THUMBNAIL);
+
+                // We only need to store the custom wallpaper that is set by the
+                // built-in wallpaper picker.
+                if (!appName) {

[tbarzic, 2016/02/04 21:31:24]

This can give false positives if the wallpaper was set by third party app on
builds that do not sync file name.

[xdai1, 2016/02/05 01:09:52]

You're right. 
Actually on a second thought I think it's unnecessary to store the custom
wallpaper here. It will be saved in the onFileStatusChanged() event anyway.

+                  WallpaperUtil.storeWallpaperToLocalFS(wallpaperFilename,
+                      reader.result, Constants.WallpaperDirNameEnum.ORIGINAL);
+                  WallpaperUtil.storeWallpaperToLocalFS(wallpaperFilename,
+                      thumbnailData, Constants.WallpaperDirNameEnum.THUMBNAIL);
+                }
                 if (onSuccess)
                   onSuccess();
               });
         };
         reader.readAsArrayBuffer(file);
       }, WallpaperUtil.onFileSystemError);
     }, function(e) {}  // fail to read file, expected due to download delay
     );
   };
   WallpaperUtil.requestSyncFS(setWallpaperFromSyncCallback);
@@ skipping 27 matching lines @@
   });
 };
 
 /**
  * Saves user's wallpaper infomation to local and sync storage. Note that local
  * value should be saved first.
  * @param {string} url The url address of wallpaper. For custom wallpaper, it is
  *     the file name.
  * @param {string} layout The wallpaper layout.
  * @param {string} source The wallpaper source.
+ * @param {string} appName The third party app name. If the current wallpaper is
+ *     set by the built-in wallpaper picker, it is set to an empty string.
  */
-WallpaperUtil.saveWallpaperInfo = function(url, layout, source) {
+WallpaperUtil.saveWallpaperInfo = function(url, layout, source, appName) {
   var wallpaperInfo = {
       url: url,
       layout: layout,
-      source: source
+      source: source,
+      appName: appName,
   };
   WallpaperUtil.saveToLocalStorage(Constants.AccessLocalWallpaperInfoKey,
                               wallpaperInfo, function() {
     WallpaperUtil.saveToSyncStorage(Constants.AccessSyncWallpaperInfoKey,
                                 wallpaperInfo);
   });
 };
 
 /**
  * Downloads resources from url. Calls onSuccess and opt_onFailure accordingly.
@@ skipping 43 matching lines @@
   chrome.wallpaperPrivate.setWallpaperIfExists(url, layout, function(exists) {
     if (exists) {
       onSuccess();
       return;
     }
 
     self.fetchURL(url, 'arraybuffer', function(xhr) {
       if (xhr.response != null) {
         chrome.wallpaperPrivate.setWallpaper(xhr.response, layout, url,
                                              onSuccess);
-        self.saveWallpaperInfo(url, layout,
-                               Constants.WallpaperSourceEnum.Online);
+        self.saveWallpaperInfo(
+            url, layout, Constants.WallpaperSourceEnum.Online, '');
       } else {
         onFailure();
       }
     }, onFailure);
   });
 };
 
 /**
  * Runs chrome.test.sendMessage in test environment. Does nothing if running
  * in production environment.
  *
  * @param {string} message Test message to send.
  */
 WallpaperUtil.testSendMessage = function(message) {
   var test = chrome.test || window.top.chrome.test;
   if (test)
     test.sendMessage(message);
 };