Bug 1491212 part 3 - Have Document.exitFullscreen return a Promise. r=smaug

Depends on D5989

Differential Revision: https://phabricator.services.mozilla.com/D5990

--HG--
extra : moz-landing-system : lando

dom/base/FullscreenChange.h

@@ -151,6 +151,35 @@ private:
   }
 };
 
+class FullscreenExit : public FullscreenChange
+{
+public:
+  static const ChangeType kType = eExit;
+
+  static UniquePtr<FullscreenExit> Create(nsIDocument* aDoc, ErrorResult& aRv)
+  {
+    RefPtr<Promise> promise = Promise::Create(aDoc->GetOwnerGlobal(), aRv);
+    return WrapUnique(new FullscreenExit(aDoc, promise.forget()));
+  }
+
+  static UniquePtr<FullscreenExit> CreateForRemote(nsIDocument* aDoc)
+  {
+    return WrapUnique(new FullscreenExit(aDoc, nullptr));
+  }
+
+  ~FullscreenExit()
+  {
+    MOZ_COUNT_DTOR(FullscreenExit);
+  }
+
+private:
+  FullscreenExit(nsIDocument* aDoc, already_AddRefed<Promise> aPromise)
+    : FullscreenChange(kType, aDoc, std::move(aPromise))
+  {
+    MOZ_COUNT_CTOR(FullscreenExit);
+  }
+};
+
 } // namespace mozilla
 
 #endif // mozilla_FullscreenRequest_h

dom/base/nsDocument.cpp

@@ -10730,10 +10730,13 @@ nsIDocument::SetFullscreenRoot(nsIDocument* aRoot)
   mFullscreenRoot = do_GetWeakReference(aRoot);
 }
 
-void
-nsIDocument::ExitFullscreen()
+already_AddRefed<Promise>
+nsIDocument::ExitFullscreen(ErrorResult& aRv)
 {
-  RestorePreviousFullscreenState();
+  UniquePtr<FullscreenExit> exit = FullscreenExit::Create(this, aRv);
+  RefPtr<Promise> promise = exit->GetPromise();
+  RestorePreviousFullscreenState(std::move(exit));
+  return promise.forget();
 }
 
 static void
@@ -10905,6 +10908,14 @@ nsIDocument::ExitFullscreenInDocTree(nsIDocument* aMaybeNotARootDoc)
   // Unlock the pointer
   UnlockPointer();
 
+  // Resolve all promises which waiting for exit fullscreen.
+  PendingFullscreenChangeList::Iterator<FullscreenExit> iter(
+    aMaybeNotARootDoc, PendingFullscreenChangeList::eDocumentsWithSameRoot);
+  while (!iter.AtEnd()) {
+    UniquePtr<FullscreenExit> exit = iter.TakeAndNext();
+    exit->MayResolvePromise();
+  }
+
   nsCOMPtr<nsIDocument> root = aMaybeNotARootDoc->GetFullscreenRoot();
   if (!root || !root->FullscreenStackTop()) {
     // If a document was detached before exiting from fullscreen, it is
@@ -10948,12 +10959,13 @@ DispatchFullscreenNewOriginEvent(nsIDocument* aDoc)
 }
 
 void
-nsIDocument::RestorePreviousFullscreenState()
+nsIDocument::RestorePreviousFullscreenState(UniquePtr<FullscreenExit> aExit)
 {
   NS_ASSERTION(!FullscreenStackTop() || !FullscreenRoots::IsEmpty(),
     "Should have at least 1 fullscreen root when fullscreen!");
 
   if (!FullscreenStackTop() || !GetWindow() || FullscreenRoots::IsEmpty()) {
+    aExit->MayRejectPromise();
     return;
   }
 
@@ -10994,6 +11006,7 @@ nsIDocument::RestorePreviousFullscreenState()
       lastDoc->mFullscreenStack.Length() == 1) {
     // If we are fully exiting fullscreen, don't touch anything here,
     // just wait for the window to get out from fullscreen first.
+    PendingFullscreenChangeList::Add(std::move(aExit));
     AskWindowToExitFullscreen(this);
     return;
   }
@@ -11021,6 +11034,7 @@ nsIDocument::RestorePreviousFullscreenState()
   for (Element* e : Reversed(exitElements)) {
     DispatchFullscreenChange(e->OwnerDoc(), e);
   }
+  aExit->MayResolvePromise();
 
   MOZ_ASSERT(newFullscreenDoc, "If we were going to exit from fullscreen on "
              "all documents in this doctree, we should've asked the window to "
@@ -11229,7 +11243,8 @@ nsresult nsIDocument::RemoteFrameFullscreenChanged(Element* aFrameElement)
 
 nsresult nsIDocument::RemoteFrameFullscreenReverted()
 {
-  RestorePreviousFullscreenState();
+  UniquePtr<FullscreenExit> exit = FullscreenExit::CreateForRemote(this);
+  RestorePreviousFullscreenState(std::move(exit));
   return NS_OK;
 }
 

dom/base/nsIDocument.h

@@ -126,6 +126,7 @@ class Encoding;
 class ErrorResult;
 class EventStates;
 class EventListenerManager;
+class FullscreenExit;
 class FullscreenRequest;
 class PendingAnimationTracker;
 class ServoStyleSet;
@@ -1811,7 +1812,8 @@ public:
    * is no former fullscreen element, this exits fullscreen, moving the
    * top-level browser window out of fullscreen mode.
    */
-  void RestorePreviousFullscreenState();
+  void RestorePreviousFullscreenState(
+    mozilla::UniquePtr<mozilla::FullscreenExit>);
 
   /**
    * Returns true if this document is a fullscreen leaf document, i.e. it
@@ -3293,7 +3295,7 @@ public:
   {
     return !!GetFullscreenElement();
   }
-  void ExitFullscreen();
+  already_AddRefed<mozilla::dom::Promise> ExitFullscreen(ErrorResult&);
   void ExitPointerLock()
   {
     UnlockPointer(this);

dom/html/test/file_fullscreen-api.html

@@ -109,7 +109,7 @@ function enter2(event) {
   // the full-screen element to the previous full-screen element. This causes
   // a fullscreenchange event.
   addFullscreenChangeContinuation("exit", exit2);
-  document.exitFullscreen();
+  promise = document.exitFullscreen();
 }
 
 function exit2(event) {
@@ -117,6 +117,7 @@ function exit2(event) {
      "Full-screen element should have rolled back.");
   is(iframe.contentDocument.fullscreenElement, null,
      "Full-screen element in subframe should be null");
+  assertPromiseResolved(promise, "in exit2");
   
   addFullscreenChangeContinuation("enter", enter3);
   promise = FULLSCREEN_ELEMENT.requestFullscreen();

dom/webidl/Document.webidl

@@ -269,10 +269,10 @@ partial interface Document {
   [BinaryName="fullscreenEnabled", NeedsCallerType]
   readonly attribute boolean mozFullScreenEnabled;
 
-  [Func="nsDocument::IsUnprefixedFullscreenEnabled"]
-  void exitFullscreen();
-  [BinaryName="exitFullscreen"]
-  void mozCancelFullScreen();
+  [Throws, Func="nsDocument::IsUnprefixedFullscreenEnabled"]
+  Promise<void> exitFullscreen();
+  [Throws, BinaryName="exitFullscreen"]
+  Promise<void> mozCancelFullScreen();
 
   // Events handlers
   [Func="nsDocument::IsUnprefixedFullscreenEnabled"]

testing/web-platform/meta/fullscreen/api/promises-reject.html.ini

@@ -1,4 +0,0 @@
-[promises-reject.html]
-  [Promises#reject 1]
-    expected: FAIL
-

testing/web-platform/meta/fullscreen/idlharness.window.js.ini

@@ -1,4 +0,0 @@
-[idlharness.window.html]
-  [Document interface: operation exitFullscreen()]
-    expected: FAIL
-