Add support for entering/exiting HTML fullscreen from OOPIFs.

third_party/WebKit/Source/core/dom/Fullscreen.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
@@ skipping 43 matching lines @@
 static bool fullscreenIsAllowedForAllOwners(const Document& document)
 {
     if (!document.frame())
         return false;
 
     for (const Frame* frame = document.frame(); frame->owner(); frame = frame->tree().parent()) {
         // TODO(alexmos): The allowfullscreen attribute will need to be
         // replicated for this to work with OOPIFs.  For now, deny fullscreen
         // access inside OOPIFs until https://crbug.com/550497 is fixed.
         if (frame->owner()->isRemote())
-            return false;
+            return true;

[alexmos, 2016/05/10 21:36:24]

This will go away once I rebase on the allowFullscreen replication CL
(https://codereview.chromium.org/1938753002/)

 
         HTMLFrameOwnerElement* owner = toHTMLFrameOwnerElement(frame->owner());
         if (!isHTMLIFrameElement(owner))
             return false;
         if (!owner->hasAttribute(allowfullscreenAttr))
             return false;
     }
     return true;
 }
 
@@ skipping 336 matching lines @@
 
 bool Fullscreen::fullscreenEnabled(Document& document)
 {
     // 4. The fullscreenEnabled attribute must return true if the context object has its
     //    fullscreen enabled flag set and fullscreen is supported, and false otherwise.
 
     // Top-level browsing contexts are implied to have their allowFullScreen attribute set.
     return fullscreenIsAllowedForAllOwners(document) && fullscreenIsSupported(document);
 }
 
-void Fullscreen::didEnterFullScreenForElement(Element* element)
+void Fullscreen::didEnterFullScreenForElement(Element* element, bool isAncestorOfFullscreenElement)
 {
     DCHECK(element);
     if (!document()->isActive())
         return;
 
     if (m_fullScreenLayoutObject)
         m_fullScreenLayoutObject->unwrapLayoutObject();
 
     m_fullScreenElement = element;
 
     // Create a placeholder block for a the full-screen element, to keep the page from reflowing
     // when the element is removed from the normal flow. Only do this for a LayoutBox, as only
     // a box will have a frameRect. The placeholder will be created in setFullScreenLayoutObject()
     // during layout.
     LayoutObject* layoutObject = m_fullScreenElement->layoutObject();
     bool shouldCreatePlaceholder = layoutObject && layoutObject->isBox();
     if (shouldCreatePlaceholder) {
         m_savedPlaceholderFrameRect = toLayoutBox(layoutObject)->frameRect();
         m_savedPlaceholderComputedStyle = ComputedStyle::clone(layoutObject->styleRef());
     }
 
+    // TODO(alexmos): When |isAncestorOfFullscreenElement| is true, some of
+    // this layout work has already been done in another process, so it should
+    // not be necessary to repeat it here.

[alexmos, 2016/05/10 21:36:24]

Namely, the wrapLayoutObject call and stuff in LayoutFullScreen::updateStyle()
is only necessary in the actual fullscreen element's frame and process (this is
the stuff that creates an anonymous flexbox with a large z-index and solid black
background).   It isn't really necessary for the parent <iframes> since those
adjust for fullscreen via UA CSS instead (see Source/core/css/fullscreen.css),
which is triggered by the setContainsFullScreenElement flag below.  I've gotten
this to work, but I'm deferring this to a followup CL to avoid overcomplicating
this one.

     if (m_fullScreenElement != document()->documentElement())
         LayoutFullScreen::wrapLayoutObject(layoutObject, layoutObject ? layoutObject->parent() : 0, document());
 
+    if (isAncestorOfFullscreenElement) {
+        DCHECK(m_fullScreenElement->isFrameOwnerElement());
+        DCHECK(toHTMLFrameOwnerElement(m_fullScreenElement)->contentFrame()->isRemoteFrame());
+        m_fullScreenElement->setContainsFullScreenElement(true);
+    }
+
     m_fullScreenElement->setContainsFullScreenElementOnAncestorsCrossingFrameBoundaries(true);
+
     document()->styleEngine().ensureFullscreenUAStyle();
     m_fullScreenElement->pseudoStateChanged(CSSSelector::PseudoFullScreen);
 
     // FIXME: This should not call updateLayoutTree.
     document()->updateLayoutTree();
 
     m_fullScreenElement->didBecomeFullscreenElement();
 
     if (document()->frame())
         document()->frame()->eventHandler().scheduleHoverStateUpdate();
 
     m_eventQueueTimer.startOneShot(0, BLINK_FROM_HERE);
 }
 
-void Fullscreen::didExitFullScreenForElement(Element*)
+void Fullscreen::didExitFullScreenForElement(bool isAncestorOfFullscreenElement)
 {
     if (!m_fullScreenElement)
         return;
 
     if (!document()->isActive())
         return;
 
     m_fullScreenElement->willStopBeingFullscreenElement();
 
+    if (isAncestorOfFullscreenElement)
+        m_fullScreenElement->setContainsFullScreenElement(false);
+
     m_fullScreenElement->setContainsFullScreenElementOnAncestorsCrossingFrameBoundaries(false);
 
     if (m_fullScreenLayoutObject)
         LayoutFullScreenItem(m_fullScreenLayoutObject).unwrapLayoutObject();
 
     document()->styleEngine().ensureFullscreenUAStyle();
     m_fullScreenElement->pseudoStateChanged(CSSSelector::PseudoFullScreen);
     m_fullScreenElement = nullptr;
 
     if (document()->frame())
@@ skipping 126 matching lines @@
 DEFINE_TRACE(Fullscreen)
 {
     visitor->trace(m_fullScreenElement);
     visitor->trace(m_fullScreenElementStack);
     visitor->trace(m_eventQueue);
     Supplement<Document>::trace(visitor);
     ContextLifecycleObserver::trace(visitor);
 }
 
 } // namespace blink