Begin tracking why layout is invalidated

Source/core/layout/LayoutText.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 172 matching lines @@
     return false;
 }
 
 void LayoutText::styleDidChange(StyleDifference diff, const ComputedStyle* oldStyle)
 {
     // There is no need to ever schedule paint invalidations from a style change of a text run, since
     // we already did this for the parent of the text run.
     // We do have to schedule layouts, though, since a style change can force us to
     // need to relayout.
     if (diff.needsFullLayout()) {
-        setNeedsLayoutAndPrefWidthsRecalc();
+        setNeedsLayoutAndPrefWidthsRecalc(LayoutInvalidationReason::StyleChange);
         m_knownToHaveNoOverflowAndNoFallbackFonts = false;
     }
 
     const ComputedStyle& newStyle = styleRef();
     ETextTransform oldTransform = oldStyle ? oldStyle->textTransform() : TTNONE;
     ETextSecurity oldSecurity = oldStyle ? oldStyle->textSecurity() : TSNONE;
     if (oldTransform != newStyle.textTransform() || oldSecurity != newStyle.textSecurity())
         transformText();
 
     // This is an optimization that kicks off font load before layout.
@@ skipping 1225 matching lines @@
     ASSERT(text);
 
     if (!force && equal(m_text.impl(), text.get()))
         return;
 
     setTextInternal(text);
     // If preferredLogicalWidthsDirty() of an orphan child is true, LayoutObjectChildList::
     // insertChildNode() fails to set true to owner. To avoid that, we call
     // setNeedsLayoutAndPrefWidthsRecalc() only if this LayoutText has parent.
     if (parent())
-        setNeedsLayoutAndPrefWidthsRecalc();
+        setNeedsLayoutAndPrefWidthsRecalc(LayoutInvalidationReason::TextChanged);
     m_knownToHaveNoOverflowAndNoFallbackFonts = false;
 
     if (AXObjectCache* cache = document().existingAXObjectCache())
         cache->textChanged(this);
 }
 
 void LayoutText::dirtyOrDeleteLineBoxesIfNeeded(bool fullLayout)
 {
     if (fullLayout)
         deleteTextBoxes();
@@ skipping 448 matching lines @@
 }
 
 void LayoutText::invalidateDisplayItemClients(const LayoutBoxModelObject& paintInvalidationContainer) const
 {
     LayoutObject::invalidateDisplayItemClients(paintInvalidationContainer);
     for (InlineTextBox* box = firstTextBox(); box; box = box->nextTextBox())
         paintInvalidationContainer.invalidateDisplayItemClientOnBacking(*box);
 }
 
 } // namespace blink