Commit 79f2dc0a authored by Nicholas Nethercote's avatar Nicholas Nethercote
Browse files

Bug 655583 - In about:memory, only remove the observer if it's been added, in... 

Bug 655583 - In about:memory, only remove the observer if it's been added, in order to avoid an assertion and/or exception.  r=bz.
parent d2396da9

toolkit/components/aboutmemory/content/aboutMemory.js

+11 −3
Original line number Diff line number Diff line
@@ -46,6 +46,8 @@ const Cu = Components.utils; 
// non-standard URL.

var gVerbose = (location.href.split(/[\?,]/).indexOf("verbose") !== -1);



var gAddedObserver = false;



function onLoad()

{

  var os = Cc["@mozilla.org/observer-service;1"].
@@ -53,16 +55,22 @@ function onLoad() 
  os.notifyObservers(null, "child-memory-reporter-request", null);



  os.addObserver(ChildMemoryListener, "child-memory-reporter-update", false);

  gAddedObserver = true;



  update();

}



function onUnload()

{

  // We need to check if the observer has been added before removing; in some

  // circumstances (eg. reloading the page quickly) it might not have because

  // onLoad might not fire.

  if (gAddedObserver) {

    var os = Cc["@mozilla.org/observer-service;1"].

        getService(Ci.nsIObserverService);

    os.removeObserver(ChildMemoryListener, "child-memory-reporter-update");

  }

}



function ChildMemoryListener(aSubject, aTopic, aData)

{