Add parsing support for display: contents, and minimum behavior similar to display: none

third_party/WebKit/Source/core/layout/LayoutObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 117 matching lines @@
 // LayoutObject associated with the Document.
 //
 // Some LayoutObjects don't have an associated Node and are called "anonymous"
 // (see the constructor below). Anonymous LayoutObjects exist for several
 // purposes but are usually required by CSS. A good example is anonymous table
 // parts (see LayoutTable for the expected structure). Anonymous LayoutObjects
 // are generated when a new child is added to the tree in addChild(). See the
 // function for some important information on this.
 //
 // Also some Node don't have an associated LayoutObjects e.g. if display: none
-// is set. For more detail, see LayoutObject::createObject that creates the
-// right LayoutObject based on the style.
+// or display: contents is set. For more detail, see LayoutObject::createObject
+// that creates the right LayoutObject based on the style.
 //
 // Because the SVG and CSS classes both inherit from this object, functions can
 // belong to either realm and sometimes to both.
 //
 // The purpose of the layout tree is to do layout (aka reflow) and store its
 // results for painting and hit-testing. Layout is the process of sizing and
 // positioning Nodes on the page. In Blink, layouts always start from a relayout
 // boundary (see objectIsRelayoutBoundary in LayoutObject.cpp). As such, we
 // need to mark the ancestors all the way to the enclosing relayout boundary in
 // order to do a correct layout.
@@ skipping 317 matching lines @@
   void showLayoutObject(StringBuilder&) const;
   void showLayoutTreeAndMark(const LayoutObject* markedObject1 = nullptr,
                              const char* markedLabel1 = nullptr,
                              const LayoutObject* markedObject2 = nullptr,
                              const char* markedLabel2 = nullptr,
                              unsigned depth = 0) const;
 #endif
 
   // This function is used to create the appropriate LayoutObject based
   // on the style, in particular 'display' and 'content'.
-  // "display: none" is the only time this function will return nullptr.
+  // "display: none" or "display: contents" are the only times this function
+  // will return nullptr.
   //
   // For renderer creation, the inline-* values create the same renderer
   // as the non-inline version. The difference is that inline-* sets
   // m_isInline during initialization. This means that
   // "display: inline-table" creates a LayoutTable, like "display: table".
   //
   // Ideally every Element::createLayoutObject would call this function to
   // respond to 'display' but there are deep rooted assumptions about
   // which LayoutObject is created on a fair number of Elements. This
   // function also doesn't handle the default association between a tag
@@ skipping 2109 matching lines @@
 CORE_EXPORT void showLineTree(const blink::LayoutObject*);
 CORE_EXPORT void showLayoutTree(const blink::LayoutObject* object1);
 // We don't make object2 an optional parameter so that showLayoutTree
 // can be called from gdb easily.
 CORE_EXPORT void showLayoutTree(const blink::LayoutObject* object1,
                                 const blink::LayoutObject* object2);
 
 #endif
 
 #endif  // LayoutObject_h