Revert of 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 b20cb00f53450ad90eacc621428e95255a665d65..ebdca0e38d66995b95607ff5c0664a124f3a6636 100644
--- a/third_party/WebKit/Source/core/dom/Fullscreen.cpp
+++ b/third_party/WebKit/Source/core/dom/Fullscreen.cpp
@@ -27,7 +27,6 @@
 
 #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"
@@ -43,9 +42,10 @@
 #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 {
@@ -196,6 +196,7 @@ bool Fullscreen::isFullScreen(Document& document)
 
 Fullscreen::Fullscreen(Document& document)
     : ContextLifecycleObserver(&document)
+    , m_fullScreenLayoutObject(nullptr)
     , m_eventQueueTimer(this, &Fullscreen::eventQueueTimerFired)
     , m_forCrossProcessDescendant(false)
 {
@@ -215,6 +216,9 @@ void Fullscreen::contextDestroyed()
 {
     m_eventQueue.clear();
 
+    if (m_fullScreenLayoutObject)
+        m_fullScreenLayoutObject->destroy();
+
     m_fullScreenElement = nullptr;
     m_fullScreenElementStack.clear();
 
@@ -482,13 +486,31 @@ 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
@@ -524,7 +546,6 @@ void Fullscreen::didExitFullscreen()
     if (!document()->isActive())
         return;
 
-    document()->removeFromTopLayer(m_fullScreenElement.get());
     m_fullScreenElement->willStopBeingFullscreenElement();
 
     if (m_forCrossProcessDescendant)
@@ -532,6 +553,9 @@ 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;
@@ -551,12 +575,28 @@ void Fullscreen::didExitFullscreen()
     m_forCrossProcessDescendant = false;
 }
 
-void Fullscreen::didUpdateSize(Element& element)
+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()
 {
-    // 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));
+    m_fullScreenLayoutObject = nullptr;
 }
 
 void Fullscreen::enqueueChangeEvent(Document& document, RequestType requestType)
@@ -641,14 +681,12 @@ 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)