[gnome-shell] Revert "background: fix asynchronous management of background loading operations"

[Adel Gadllah <agadllah src gnome org>]

commit 062235f3a7dc75935b6b21c33828bec1733d4a04
Author: Adel Gadllah <adel gadllah gmail com>
Date:   Thu Aug 15 21:51:46 2013 +0200

    Revert "background: fix asynchronous management of background loading operations"
    
    This reverts commit 1020d8a0f8523a04d8336b1348388b8b242e414f.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=704646

 js/ui/background.js |   69 ++++++++++++++++++--------------------------------
 1 files changed, 25 insertions(+), 44 deletions(-)
---
diff --git a/js/ui/background.js b/js/ui/background.js
index 13343c6..1d9ab7c 100644
--- a/js/ui/background.js
+++ b/js/ui/background.js
@@ -142,40 +142,33 @@ const BackgroundCache = new Lang.Class({
                                         cancellable: null,
                                         onFinished: null });
 
-        let fileLoad = { filename: params.filename,
-                         style: params.style,
-                         shouldCopy: false,
-                         monitorIndex: params.monitorIndex,
-                         effects: params.effects,
-                         onFinished: params.onFinished,
-                         cancellable: new Gio.Cancellable(), };
-        this._pendingFileLoads.push(fileLoad);
-
-        if (params.cancellable) {
-            params.cancellable.connect(Lang.bind(this, function(c) {
-               fileLoad.cancellable.cancel();
-            }));
+        for (let i = 0; i < this._pendingFileLoads.length; i++) {
+            if (this._pendingFileLoads[i].filename == params.filename &&
+                this._pendingFileLoads[i].style == params.style) {
+                this._pendingFileLoads[i].callers.push({ shouldCopy: true,
+                                                         monitorIndex: params.monitorIndex,
+                                                         effects: params.effects,
+                                                         onFinished: params.onFinished });
+                return;
+            }
         }
 
+        this._pendingFileLoads.push({ filename: params.filename,
+                                      style: params.style,
+                                      callers: [{ shouldCopy: false,
+                                                  monitorIndex: params.monitorIndex,
+                                                  effects: params.effects,
+                                                  onFinished: params.onFinished }] });
+
         let content = new Meta.Background({ meta_screen: global.screen,
                                             monitor: params.monitorIndex,
                                             effects: params.effects });
 
         content.load_file_async(params.filename,
                                 params.style,
-                                fileLoad.cancellable,
+                                params.cancellable,
                                 Lang.bind(this,
                                           function(object, result) {
-                                              if (fileLoad.cancellable.is_cancelled()) {
-                                                  if (params.cancellable && 
params.cancellable.is_cancelled()) {
-                                                      if (params.onFinished)
-                                                          params.onFinished(null);
-                                                      this._removePendingFileLoad(fileLoad);
-                                                      return;
-                                                  }
-                                                  return;
-                                              }
-
                                               try {
                                                   content.load_file_finish(result);
 
@@ -185,25 +178,22 @@ const BackgroundCache = new Lang.Class({
                                                   content = null;
                                               }
 
-                                              let needsCopy = false;
                                               for (let i = 0; i < this._pendingFileLoads.length; i++) {
                                                   let pendingLoad = this._pendingFileLoads[i];
                                                   if (pendingLoad.filename != params.filename ||
                                                       pendingLoad.style != params.style)
                                                       continue;
 
-                                                  if (pendingLoad.cancellable.is_cancelled())
-                                                      continue;
+                                                  for (let j = 0; j < pendingLoad.callers.length; j++) {
+                                                      if (pendingLoad.callers[j].onFinished) {
+                                                          if (content && pendingLoad.callers[j].shouldCopy) {
+                                                              content = 
object.copy(pendingLoad.callers[j].monitorIndex,
+                                                                                    
pendingLoad.callers[j].effects);
 
-                                                  pendingLoad.cancellable.cancel();
-                                                  if (pendingLoad.onFinished) {
-                                                      if (content && needsCopy) {
-                                                          content = object.copy(pendingLoad.monitorIndex,
-                                                                                pendingLoad.effects);
-                                                      }
+                                                          }
 
-                                                      needsCopy = true;
-                                                      pendingLoad.onFinished(content);
+                                                          pendingLoad.callers[j].onFinished(content);
+                                                      }
                                                   }
 
                                                   this._pendingFileLoads.splice(i, 1);
@@ -211,15 +201,6 @@ const BackgroundCache = new Lang.Class({
                                           }));
     },
 
-    _removePendingFileLoad: function(fileLoad) {
-        for (let i = 0; i < this._pendingFileLoads.length; i++) {
-            if (this._pendingFileLoads[i].cancellable == fileLoad.cancellable) {
-                this._pendingFileLoads.splice(i, 1);
-                break;
-            }
-        }
-    },
-
     getImageContent: function(params) {
         params = Params.parse(params, { monitorIndex: 0,
                                         style: null,