InPrePaint document state and PrePaintTreeWalk class

third_party/WebKit/Source/core/dom/DocumentLifecycle.h

Index: third_party/WebKit/Source/core/dom/DocumentLifecycle.h
diff --git a/third_party/WebKit/Source/core/dom/DocumentLifecycle.h b/third_party/WebKit/Source/core/dom/DocumentLifecycle.h
index b744be68a65bcca8d90c00c4d72e2ee6d54a0ae0..e7c0949ad6d1d1a8411dfc3ca4cdbbc1e8e6caf6 100644
--- a/third_party/WebKit/Source/core/dom/DocumentLifecycle.h
+++ b/third_party/WebKit/Source/core/dom/DocumentLifecycle.h
@@ -67,12 +67,12 @@ public:
         InPaintInvalidation,
         PaintInvalidationClean,
 
-        // When RuntimeEnabledFeatures::slimmingPaintV2Enabled.
-        InUpdatePaintProperties,
-        UpdatePaintPropertiesClean,
+        // In InPrePaint step, any data needed by painting are prepared.
+        // When RuntimeEnabledFeatures::slimmingPaintV2Enabled, paint property trees are built.
+        // Otherwise these steps are not applicable.
+        InPrePaint,
+        PrePaintClean,
 
-        // When RuntimeEnabledFeatures::slimmingPaintSynchronizedPaintingEnabled
-        // (implied by slimmingPaintV2Enabled).
         InPaint,
         PaintClean,
 
@@ -197,7 +197,7 @@ inline bool DocumentLifecycle::stateAllowsTreeMutations() const
     return m_state != InStyleRecalc
         && m_state != InPerformLayout
         && m_state != InCompositingUpdate
-        && m_state != InUpdatePaintProperties
+        && m_state != InPrePaint
         && m_state != InPaint;
 }
 
@@ -221,7 +221,7 @@ inline bool DocumentLifecycle::stateAllowsDetach() const
         || m_state == LayoutClean
         || m_state == CompositingClean
         || m_state == PaintInvalidationClean
-        || m_state == UpdatePaintPropertiesClean
+        || m_state == PrePaintClean
         || m_state == PaintClean
         || m_state == Stopping;
 }
@@ -231,7 +231,7 @@ inline bool DocumentLifecycle::stateAllowsLayoutInvalidation() const
     return m_state != InPerformLayout
         && m_state != InCompositingUpdate
         && m_state != InPaintInvalidation
-        && m_state != InUpdatePaintProperties
+        && m_state != InPrePaint
         && m_state != InPaint;
 }