Add Blink.PrePaint.UpdateTime as an alias of Blink.PaintInvalidation.UpdateTime

third_party/WebKit/Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 3172 matching lines @@
 
   // Ensure that we become visually non-empty eventually.
   // TODO(esprehn): This should check isRenderingReady() instead.
   if (frame().document()->hasFinishedParsing() &&
       frame().loader().stateMachine()->committedFirstRealDocumentLoad())
     m_isVisuallyNonEmpty = true;
 }
 
 void FrameView::invalidateTreeIfNeededRecursive() {
   SCOPED_BLINK_UMA_HISTOGRAM_TIMER("Blink.PaintInvalidation.UpdateTime");
-  invalidateTreeIfNeededRecursiveInternal();
+  {
+    // For comparison to SlimmingPaintInvalidation.
+    SCOPED_BLINK_UMA_HISTOGRAM_TIMER("Blink.PrePaint.UpdateTime");
+    invalidateTreeIfNeededRecursiveInternal();
+  }
 }
 
 void FrameView::invalidateTreeIfNeededRecursiveInternal() {
   DCHECK(!RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled());
   CHECK(layoutView());
 
   // We need to stop recursing here since a child frame view might not be
   // throttled even though we are (e.g., it didn't compute its visibility yet).
   if (shouldThrottleRendering())
     return;
@@ skipping 1785 matching lines @@
   // This is the top-level frame, so no mapping necessary.
   if (m_frame->isMainFrame())
     return;
 
   LayoutRect viewportIntersectionRect(remoteViewportIntersection());
   transformState.move(
       LayoutSize(-viewportIntersectionRect.x(), -viewportIntersectionRect.y()));
 }
 
 }  // namespace blink