Add option to dump line box tree when dumping layout tree.

Source/core/layout/LayoutTreeAsText.h

 /*
  * Copyright (C) 2003, 2006, 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 15 matching lines @@
 #ifndef LayoutTreeAsText_h
 #define LayoutTreeAsText_h
 
 #include "core/CoreExport.h"
 #include "platform/text/TextStream.h"
 #include "wtf/Forward.h"
 
 namespace blink {
 
 class Color;
+class DeprecatedPaintLayer;
 class Element;
 class LayoutRect;
 class LocalFrame;
 class Node;
-class DeprecatedPaintLayer;
+class LayoutBlockFlow;
 class LayoutObject;
 class TextStream;
 
 enum LayoutAsTextBehaviorFlags {
     LayoutAsTextBehaviorNormal = 0,
     LayoutAsTextShowAllLayers = 1 << 0, // Dump all layers, not just those that would paint.
     LayoutAsTextShowLayerNesting = 1 << 1, // Annotate the layer lists.
     LayoutAsTextShowCompositedLayers = 1 << 2, // Show which layers are composited.
     LayoutAsTextShowAddresses = 1 << 3, // Show layer and layoutObject addresses.
     LayoutAsTextShowIDAndClass = 1 << 4, // Show id and class attributes
     LayoutAsTextPrintingMode = 1 << 5, // Dump the tree in printing mode.
     LayoutAsTextDontUpdateLayout = 1 << 6, // Don't update layout, to make it safe to call showLayerTree() from the debugger inside layout or painting code.
-    LayoutAsTextShowLayoutState = 1 << 7 // Print the various 'needs layout' bits on layoutObjects.
+    LayoutAsTextShowLayoutState = 1 << 7, // Print the various 'needs layout' bits on layoutObjects.
+    LayoutAsTextShowLineTrees = 1 << 8 // Dump the line trees for each LayoutBlockFlow.
 };
 typedef unsigned LayoutAsTextBehavior;
 
 // You don't need pageWidthInPixels if you don't specify LayoutAsTextInPrintingMode.
 CORE_EXPORT String externalRepresentation(LocalFrame*, LayoutAsTextBehavior = LayoutAsTextBehaviorNormal);
 CORE_EXPORT String externalRepresentation(Element*, LayoutAsTextBehavior = LayoutAsTextBehaviorNormal);
 void write(TextStream&, const LayoutObject&, int indent = 0, LayoutAsTextBehavior = LayoutAsTextBehaviorNormal);
 
 class LayoutTreeAsText {
 // FIXME: This is a cheesy hack to allow easy access to ComputedStyle colors.  It won't be needed if we convert
 // it to use visitedDependentColor instead. (This just involves rebaselining many results though, so for now it's
 // not being done).
 public:
 static void writeLayoutObject(TextStream&, const LayoutObject&, LayoutAsTextBehavior);
 static void writeLayers(TextStream&, const DeprecatedPaintLayer* rootLayer, DeprecatedPaintLayer*, const LayoutRect& paintDirtyRect, int indent = 0, LayoutAsTextBehavior = LayoutAsTextBehaviorNormal);
+static void writeLineBoxTree(TextStream&, const LayoutBlockFlow&, int indent = 0);
 };
 
 // Helper function shared with SVGLayoutTreeAsText
 String quoteAndEscapeNonPrintables(const String&);
 
 CORE_EXPORT String counterValueForElement(Element*);
 
 CORE_EXPORT String markerTextForListItem(Element*);
 
 CORE_EXPORT String nodePositionAsStringForTesting(Node*);
 
 TextStream& operator<<(TextStream&, const Color&);
 
 } // namespace blink
 
 #endif // LayoutTreeAsText_h