Slimming Paint phase 2 compositing algorithm plumbing & skeleton display list API.

Source/core/dom/DocumentLifecycle.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 47 matching lines @@
         InPerformLayout,
         AfterPerformLayout,
         LayoutClean,
 
         InCompositingUpdate,
         CompositingClean,
 
         InPaintInvalidation,
         PaintInvalidationClean,
 
+        // TODO(chrishtr): add lifecycle states for scrolling update and paint.

[Ian Vollick, 2015/07/23 22:53:06]

This sounds exciting. Where will the scrolling update fit in the document
lifecycle? After paint, before compositing?

[chrishtr, 2015/07/23 23:57:39]

t has to be after compositing also, to map scrolling requests to the right
backing. This is what we do pre-slimming-paint also:

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

+
         // Once the document starts shuting down, we cannot return
         // to the style/layout/compositing states.
         Stopping,
         Stopped,
         Disposed,
     };
 
     class Scope {
         WTF_MAKE_NONCOPYABLE(Scope);
     public:
@@ skipping 108 matching lines @@
 inline bool DocumentLifecycle::stateAllowsLayoutInvalidation() const
 {
     return m_state != InPerformLayout
         && m_state != InCompositingUpdate
         && m_state != InPaintInvalidation;
 }
 
 } // namespace blink
 
 #endif