Add layout states to DocumentLifecycle state machine

Source/core/dom/Document.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, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 1531 matching lines @@
         return 0;
     }
     return TreeWalker::create(root, whatToShow, filter);
 }
 
 bool Document::shouldCallRecalcStyleForDocument()
 {
     return needsStyleRecalc() || childNeedsStyleRecalc() || childNeedsDistributionRecalc() || !m_useElementsNeedingUpdate.isEmpty() || childNeedsStyleInvalidation();
 }
 
+bool Document::shouldScheduleStyleRecalc()
+{
+    if (!isActive())
+        return false;
+    if (hasPendingStyleRecalc())
+        return false;
+    if (inStyleRecalc())
+        return false;
+    // InPreLayout will recalc style itself. There's no reason to schedule another recalc.
+    if (m_lifecycle.state() == DocumentLifecycle::InPreLayout)
+        return false;
+    if (!shouldScheduleLayout())
+        return false;
+    return true;
+}
+
 void Document::scheduleStyleRecalc()
 {
-    if (hasPendingStyleRecalc() || !isActive() || inStyleRecalc() || !shouldScheduleLayout())
+    if (!shouldScheduleStyleRecalc())
         return;
 
     ASSERT(shouldCallRecalcStyleForDocument());
 
     view()->scheduleAnimation();
-    m_lifecycle.rewindTo(DocumentLifecycle::StyleRecalcPending);
+    m_lifecycle.advanceTo(DocumentLifecycle::StyleRecalcPending);
 
     InspectorInstrumentation::didScheduleStyleRecalculation(this);
 }
 
 bool Document::hasPendingForcedStyleRecalc() const
 {
     return hasPendingStyleRecalc() && !inStyleRecalc() && styleChangeType() >= SubtreeStyleChange;
 }
 
 void Document::updateDistributionIfNeeded()
@@ skipping 191 matching lines @@
         if (m_styleEngine->hasResolver()) {
             // Pseudo element removal and similar may only work with these flags still set. Reset them after the style recalc.
             StyleResolver& resolver = m_styleEngine->ensureResolver();
             m_styleEngine->resetCSSFeatureFlags(resolver.ensureRuleFeatureSet());
             resolver.clearStyleSharingList();
         }
 
         ASSERT(!needsStyleRecalc());
         ASSERT(!childNeedsStyleRecalc());
         ASSERT(inStyleRecalc());
-        m_lifecycle.advanceTo(DocumentLifecycle::Clean);
+        m_lifecycle.advanceTo(DocumentLifecycle::StyleClean);
     }
 
     InspectorInstrumentation::didRecalculateStyle(cookie);
 
     // As a result of the style recalculation, the currently hovered element might have been
     // detached (for example, by setting display:none in the :hover style), schedule another mouseMove event
     // to check if any other elements ended up under the mouse pointer due to re-layout.
     if (hoverNode() && !hoverNode()->renderer() && frame())
         frame()->eventHandler().dispatchFakeMouseMoveEventSoon();
 
@@ skipping 259 matching lines @@
 
     m_renderView = new RenderView(this);
     setRenderer(m_renderView);
 
     m_renderView->setIsInWindow(true);
     m_renderView->setStyle(StyleResolver::styleForDocument(*this));
     view()->updateCompositingLayersAfterStyleChange();
 
     ContainerNode::attach(context);
 
-    m_lifecycle.advanceTo(DocumentLifecycle::Clean);
+    m_lifecycle.advanceTo(DocumentLifecycle::StyleClean);
 }
 
 void Document::detach(const AttachContext& context)
 {
     ASSERT(isActive());
     m_lifecycle.advanceTo(DocumentLifecycle::Stopping);
 
     if (page())
         page()->documentDetached(this);
 
@@ skipping 3335 matching lines @@
 void Document::defaultEventHandler(Event* event)
 {
     if (frame() && frame()->remotePlatformLayer()) {
         frame()->chromeClient().forwardInputEvent(this, event);
         return;
     }
     Node::defaultEventHandler(event);
 }
 
 } // namespace WebCore