import changes from `dev' branch of rmottola/Arctic-Fox:

- Bug 524674, nsIEventListenerService: tracking of dynamically added and removed event listeners, r=masayuki (a1779bcaf)
- Bug 418986 - Resist fingerprinting by preventing exposure of screen and system info. r=mrbkap, r=heycam (97710708a)
- bug 1171785 create nsContentUtils::RunInStableState helper r=bholley (c71678a0e)
- bug 1172377 change RunInStableState API to receive ownership of nsIRunnable r=roc (3d5c72cac)
- bug 1171785 use nsContentUtils::RunInStableState() r=bholley (1c0acca87)
- Bug 1172784 (part 1) - Remove unused argument from UnmarkGrayJSListenersInCCGenerationDocuments(). r=mccr8. (a3a26ec9f)
- Bug 1172784 (part 2) - Remove PL_DHashTableEnumerate use from nsContentUtils. r=mccr8. (792b83f8e)
- Bug 1171832 - Remove PL_DHashTableEnumerator use from nsDocument. r=smaug. (eb265bb3a)
- Bug 819090 - Convert nsRefMapEntry::mRefContentList to nsTArray. r=froydnj (509060d38)
- Bug 819090 - Convert BroadcasterMapEntry::mListeners to nsTArray. r=froydnj (6b1bd7232)
- Bug 819090 - Convert nsDocument::mIdContentList to nsTArray. r=froydnj (41ebb3a64)
- Bug 819090 - Remove nsVoidArray.{cpp,h}. r=froydnj (6038b4fc7)
- Bug 1199143 - Inline heavyweight functions. r=shu (798a24e44)
- bug 1150136 - rel=preconnect from html parser r=hsivonen (1a078efcb)
- Bug 1135812 - Make picture element react to viewport changes. r=dbaron,johns (4b405d69c)
- add missing testcase (cb6c04747)

dom/html/HTMLMediaElement.cpp

@@ -60,8 +60,6 @@
 #include "Layers.h"
 #include <limits>
 #include "nsIAsyncVerifyRedirectCallback.h"
-#include "nsIAppShell.h"
-#include "nsWidgetsCID.h"
 #include "nsMediaFragmentURIParser.h"
 #include "nsURIHashKey.h"
 #include "nsJSUtils.h"
@@ -741,13 +739,10 @@ public:
   }
 };
 
-static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
-
 void HTMLMediaElement::RunInStableState(nsIRunnable* aRunnable)
 {
   nsCOMPtr<nsIRunnable> event = new nsSyncSection(this, aRunnable);
-  nsCOMPtr<nsIAppShell> appShell = do_GetService(kAppShellCID);
-  appShell->RunInStableState(event);
+  nsContentUtils::RunInStableState(event.forget());
 }
 
 void HTMLMediaElement::QueueLoadFromSourceTask()