Statistics of LayoutBox rare data reasons

third_party/WebKit/Source/core/layout/LayoutBox.cpp

Index: third_party/WebKit/Source/core/layout/LayoutBox.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBox.cpp b/third_party/WebKit/Source/core/layout/LayoutBox.cpp
index 9a074fa73dc3324ba23bfe504b34ac13fc40521c..8059142c4179b18e434fd57d8ddb036ea0db40b1 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBox.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBox.cpp
@@ -102,6 +102,7 @@ LayoutBox::LayoutBox(ContainerNode* node)
       m_maxPreferredLogicalWidth(-1),
       m_inlineBoxWrapper(nullptr) {
   setIsBox();
+  m_rareStat.addReason(ReasonLBAll);
 }
 
 PaintLayerType LayoutBox::layerTypeRequired() const {
@@ -1235,11 +1236,13 @@ bool LayoutBox::hasOverrideLogicalContentWidth() const {
 void LayoutBox::setOverrideLogicalContentHeight(LayoutUnit height) {
   ASSERT(height >= 0);
   ensureRareData().m_overrideLogicalContentHeight = height;
+  m_rareStat.addReason(ReasonLBOverrideSize);
 }
 
 void LayoutBox::setOverrideLogicalContentWidth(LayoutUnit width) {
   ASSERT(width >= 0);
   ensureRareData().m_overrideLogicalContentWidth = width;
+  m_rareStat.addReason(ReasonLBOverrideSize);
 }
 
 void LayoutBox::clearOverrideLogicalContentHeight() {
@@ -2105,6 +2108,7 @@ void LayoutBox::setSpannerPlaceholder(
   // Not expected to change directly from one spanner to another.
   CHECK(!m_rareData || !m_rareData->m_spannerPlaceholder);
   ensureRareData().m_spannerPlaceholder = &placeholder;
+  m_rareStat.addReason(ReasonLBSpannerPlaceholder);
 }
 
 void LayoutBox::clearSpannerPlaceholder() {
@@ -2117,6 +2121,8 @@ void LayoutBox::setPaginationStrut(LayoutUnit strut) {
   if (!strut && !m_rareData)
     return;
   ensureRareData().m_paginationStrut = strut;
+  if (strut)
+    m_rareStat.addReason(ReasonLBPaginationStrut);
 }
 
 bool LayoutBox::isBreakBetweenControllable(EBreakBetween breakValue) const {
@@ -5422,6 +5428,8 @@ void LayoutBox::setOffsetToNextPage(LayoutUnit offset) {
   if (!m_rareData && !offset)
     return;
   ensureRareData().m_offsetToNextPage = offset;
+  if (offset)
+    m_rareStat.addReason(ReasonLBPageOffset);
 }
 
 void LayoutBox::logicalExtentAfterUpdatingLogicalWidth(
@@ -5591,6 +5599,8 @@ void LayoutBox::setPercentHeightContainer(LayoutBlock* container) {
   if (!container && !m_rareData)
     return;
   ensureRareData().m_percentHeightContainer = container;
+  if (container)
+    m_rareStat.addReason(ReasonLBPercentHeightContainer);
 }
 
 void LayoutBox::removeFromPercentHeightContainer() {