Reland "Implement FullScreen using top layer."

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

Index: third_party/WebKit/Source/core/dom/Fullscreen.cpp
diff --git a/third_party/WebKit/Source/core/dom/Fullscreen.cpp b/third_party/WebKit/Source/core/dom/Fullscreen.cpp
index 0c73478e86575a54db91d9835de4918f346b4416..fcc3315cde0d159175cb800447c5d4711d5c3ae5 100644
--- a/third_party/WebKit/Source/core/dom/Fullscreen.cpp
+++ b/third_party/WebKit/Source/core/dom/Fullscreen.cpp
@@ -27,6 +27,7 @@
 
 #include "core/dom/Fullscreen.h"
 
+#include "bindings/core/v8/ExceptionMessages.h"
 #include "core/HTMLNames.h"
 #include "core/dom/Document.h"
 #include "core/dom/ElementTraversal.h"
@@ -42,10 +43,9 @@
 #include "core/html/HTMLMediaElement.h"
 #include "core/input/EventHandler.h"
 #include "core/inspector/ConsoleMessage.h"
-#include "core/layout/LayoutBlockFlow.h"
-#include "core/layout/LayoutFullScreen.h"
-#include "core/layout/api/LayoutFullScreenItem.h"
 #include "core/page/ChromeClient.h"
+#include "core/page/Page.h"
+#include "core/style/ComputedStyle.h"
 #include "platform/UserGestureIndicator.h"
 
 namespace blink {
@@ -196,7 +196,6 @@ bool Fullscreen::isFullScreen(Document& document)
 
 Fullscreen::Fullscreen(Document& document)
     : ContextLifecycleObserver(&document)
-    , m_fullScreenLayoutObject(nullptr)
     , m_eventQueueTimer(this, &Fullscreen::eventQueueTimerFired)
     , m_forCrossProcessDescendant(false)
 {
@@ -216,9 +215,6 @@ void Fullscreen::contextDestroyed()
 {
     m_eventQueue.clear();
 
-    if (m_fullScreenLayoutObject)
-        m_fullScreenLayoutObject->destroy();
-
     m_fullScreenElement = nullptr;
     m_fullScreenElementStack.clear();
 
@@ -486,31 +482,13 @@ bool Fullscreen::fullscreenEnabled(Document& document)
 void Fullscreen::didEnterFullscreenForElement(Element* element)
 {
     DCHECK(element);
+    DCHECK(element->isInTopLayer());
+
     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 |m_forCrossProcessDescendant| is true, some of
-    // this layout work has already been done in another process, so it should
-    // not be necessary to repeat it here.
-    if (m_fullScreenElement != document()->documentElement())
-        LayoutFullScreen::wrapLayoutObject(layoutObject, layoutObject ? layoutObject->parent() : 0, document());
-
     // When |m_forCrossProcessDescendant| is true, m_fullScreenElement
     // corresponds to the HTMLFrameOwnerElement for the out-of-process iframe
     // that contains the actual fullscreen element.   Hence, it must also set
@@ -546,6 +524,7 @@ void Fullscreen::didExitFullscreen()
     if (!document()->isActive())
         return;
 
+    document()->removeFromTopLayer(m_fullScreenElement.get());
     m_fullScreenElement->willStopBeingFullscreenElement();
 
     if (m_forCrossProcessDescendant)
@@ -553,9 +532,6 @@ void Fullscreen::didExitFullscreen()
 
     m_fullScreenElement->setContainsFullScreenElementOnAncestorsCrossingFrameBoundaries(false);
 
-    if (m_fullScreenLayoutObject)
-        LayoutFullScreenItem(m_fullScreenLayoutObject).unwrapLayoutObject();
-
     document()->styleEngine().ensureFullscreenUAStyle();
     m_fullScreenElement->pseudoStateChanged(CSSSelector::PseudoFullScreen);
     m_fullScreenElement = nullptr;
@@ -575,28 +551,12 @@ void Fullscreen::didExitFullscreen()
     m_forCrossProcessDescendant = false;
 }
 
-void Fullscreen::setFullScreenLayoutObject(LayoutFullScreen* layoutObject)
-{
-    if (layoutObject == m_fullScreenLayoutObject)
-        return;
-
-    if (layoutObject && m_savedPlaceholderComputedStyle) {
-        layoutObject->createPlaceholder(m_savedPlaceholderComputedStyle.release(), m_savedPlaceholderFrameRect);
-    } else if (layoutObject && m_fullScreenLayoutObject && m_fullScreenLayoutObject->placeholder()) {
-        LayoutBlockFlow* placeholder = m_fullScreenLayoutObject->placeholder();
-        layoutObject->createPlaceholder(ComputedStyle::clone(placeholder->styleRef()), placeholder->frameRect());
-    }
-
-    if (m_fullScreenLayoutObject)
-        m_fullScreenLayoutObject->unwrapLayoutObject();
-    DCHECK(!m_fullScreenLayoutObject);
-
-    m_fullScreenLayoutObject = layoutObject;
-}
-
-void Fullscreen::fullScreenLayoutObjectDestroyed()
+void Fullscreen::didUpdateSize(Element& element)
 {
-    m_fullScreenLayoutObject = nullptr;
+    // StyleAdjuster will set the size so we need to do a style recalc.
+    // Normally changing size means layout so just doing a style recalc is a
+    // bit surprising.
+    element.setNeedsStyleRecalc(LocalStyleChange, StyleChangeReasonForTracing::create(StyleChangeReason::FullScreen));
 }
 
 void Fullscreen::enqueueChangeEvent(Document& document, RequestType requestType)
@@ -681,12 +641,14 @@ void Fullscreen::popFullscreenElementStack()
     if (m_fullScreenElementStack.isEmpty())
         return;
 
+    document()->removeFromTopLayer(m_fullScreenElementStack.last().first.get());
     m_fullScreenElementStack.removeLast();
 }
 
 void Fullscreen::pushFullscreenElementStack(Element& element, RequestType requestType)
 {
     m_fullScreenElementStack.append(std::make_pair(&element, requestType));
+    document()->addToTopLayer(&element);
 }
 
 DEFINE_TRACE(Fullscreen)