Bug 290648 make nsITransfer::init take an nsICancelable, and remove the observer attribute

r=bz sr=darin a=asa

toolkit/components/downloads/public/nsIDownload.idl

@@ -41,11 +41,11 @@
 interface nsIURI;
 interface nsILocalFile;
 interface nsIObserver;
-interface nsIWebBrowserPersist;
+interface nsICancelable;
 interface nsIWebProgressListener;
 interface nsIMIMEInfo;
 
-[scriptable, uuid(4584178b-ebbd-4d5e-91d3-aa676c2291d2)]
+[scriptable, uuid(1cb42fb4-f092-4a0e-8930-6c06a524da07)]
 interface nsIDownload : nsITransfer {
     
     /**
@@ -81,13 +81,10 @@ interface nsIDownload : nsITransfer {
     readonly attribute nsIURI target;
  
     /**
-     * Optional. If set, it will be used for cancellation, and the transfer
-     * will be set as its listener.  If not, |observer| should be set to listen
-     * and respond accordingly to topics like oncancel, and the client promises
-     * to set the transfer item as the listener for whatever transfer component
-     * is being used.
+     * Object that can be used to cancel the download.
+     * Will be null after the download is finished.
      */
-    readonly attribute nsIWebBrowserPersist persist;
+    readonly attribute nsICancelable cancelable;
 
     /**
      * The user-readable description of the transfer.

xpfe/components/download-manager/public/nsIProgressDialog.idl

@@ -40,6 +40,7 @@
 #include "nsIDownload.idl"
 
 interface nsIDOMWindow;
+interface nsIObserver;
 
 /* nsIProgressDialog
  *
@@ -62,7 +63,7 @@ interface nsIDOMWindow;
  *      not need to hold a reference to it.
  */
 
-[scriptable, uuid(80183bd3-b9e8-45a6-a2ee-1449bc0d4253)]
+[scriptable, uuid(20e790a2-76c6-462d-851a-22ab6cbbe48b)]
 interface nsIProgressDialog : nsIDownload {
    /**
     * Open the dialog
@@ -80,6 +81,15 @@ interface nsIProgressDialog : nsIDownload {
     */
    attribute PRBool cancelDownloadOnClose;
 
+   /**
+    * Observer for this dialog. If set, receives the following topics:
+    *   oncancel - observer should cancel the transfer
+    *   onpause  - observer should suspend the transfer
+    *   onresume - observer should resume the suspended transfer
+    * For each of those, the subject will be the nsIProgressDialog.
+    */
+   attribute nsIObserver observer;
+
   /**
    * The dialog object itself.  This might be null if the dialog isn't
    * open yet, or has been closed.