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)

widget/nsBaseAppShell.cpp

@@ -378,7 +378,8 @@ nsBaseAppShell::RunSyncSectionsInternal(bool aStable,
 }
 
 void
-nsBaseAppShell::ScheduleSyncSection(nsIRunnable* aRunnable, bool aStable)
+nsBaseAppShell::ScheduleSyncSection(already_AddRefed<nsIRunnable> aRunnable,
+                                    bool aStable)
 {
   NS_ASSERTION(NS_IsMainThread(), "Should be on main thread.");
 
@@ -435,16 +436,16 @@ nsBaseAppShell::Observe(nsISupports *subject, const char *topic,
   return NS_OK;
 }
 
-NS_IMETHODIMP
-nsBaseAppShell::RunInStableState(nsIRunnable* aRunnable)
+void
+nsBaseAppShell::RunInStableState(already_AddRefed<nsIRunnable> aRunnable)
 {
-  ScheduleSyncSection(aRunnable, true);
-  return NS_OK;
+  ScheduleSyncSection(mozilla::Move(aRunnable), true);
 }
 
 NS_IMETHODIMP
 nsBaseAppShell::RunBeforeNextEvent(nsIRunnable* aRunnable)
 {
-  ScheduleSyncSection(aRunnable, false);
+  nsCOMPtr<nsIRunnable> runnable = aRunnable;
+  ScheduleSyncSection(runnable.forget(), false);
   return NS_OK;
 }