FirstMeaningfulPaint UMA

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 211 matching lines @@
     m_postLayoutTasksTimer.stop();
     m_updateWidgetsTimer.stop();
     m_firstLayout = true;
     m_safeToPropagateScrollToParent = true;
     m_lastViewportSize = IntSize();
     m_lastZoomFactor = 1.0f;
     m_trackedObjectPaintInvalidations = wrapUnique(s_initialTrackAllPaintInvalidations ? new Vector<ObjectPaintInvalidation> : nullptr);
     m_visuallyNonEmptyCharacterCount = 0;
     m_visuallyNonEmptyPixelCount = 0;
     m_isVisuallyNonEmpty = false;
+    m_layoutObjectCounter.reset();
     clearFragmentAnchor();
     m_viewportConstrainedObjects.reset();
     m_layoutSubtreeRootList.clear();
     m_orthogonalWritingModeRootList.clear();
 }
 
 // Call function for each non-throttled frame view in pre tree order.
 // Note it needs a null check of the frame's layoutView to access it in case of detached frames.
 template <typename Function>
 void FrameView::forAllNonThrottledFrameViews(const Function& function)
@@ skipping 620 matching lines @@
     value->setInteger("approximateBlankCharacterCount", FontFaceSet::approximateBlankCharacterCount(*m_frame->document()));
     return value;
 }
 
 #define PERFORM_LAYOUT_TRACE_CATEGORIES "blink,benchmark," TRACE_DISABLED_BY_DEFAULT("blink.debug.layout")
 
 void FrameView::performLayout(bool inSubtreeLayout)
 {
     ASSERT(inSubtreeLayout || m_layoutSubtreeRootList.isEmpty());
 
+    int contentsHeightBeforeLayout = layoutViewItem().documentRect().height();
     TRACE_EVENT_BEGIN1(PERFORM_LAYOUT_TRACE_CATEGORIES, "FrameView::performLayout",
-        "contentsHeightBeforeLayout", layoutViewItem().documentRect().height());
+        "contentsHeightBeforeLayout", contentsHeightBeforeLayout);
     prepareLayoutAnalyzer();
 
     ScriptForbiddenScope forbidScript;
 
     ASSERT(!isInPerformLayout());
     lifecycle().advanceTo(DocumentLifecycle::InPerformLayout);
 
     // performLayout is the actual guts of layout().
     // FIXME: The 300 other lines in layout() probably belong in other helper functions
     // so that a single human could understand what layout() is actually doing.
@@ skipping 21 matching lines @@
     } else {
         layoutFromRootObject(*layoutView());
     }
 
     m_frame->document()->fetcher()->updateAllImageResourcePriorities();
 
     lifecycle().advanceTo(DocumentLifecycle::AfterPerformLayout);
 
     TRACE_EVENT_END1(PERFORM_LAYOUT_TRACE_CATEGORIES, "FrameView::performLayout",
         "counters", analyzerCounters());
+    FirstMeaningfulPaintDetector::from(*m_frame->document()).computeLayoutSignificance(m_layoutObjectCounter, contentsHeightBeforeLayout, layoutViewItem().documentRect().height(), visibleHeight());
 }
 
 void FrameView::scheduleOrPerformPostLayoutTasks()
 {
     if (m_postLayoutTasksTimer.isActive())
         return;
 
     if (!m_inSynchronousPostLayout) {
         m_inSynchronousPostLayout = true;
         // Calls resumeScheduledEvents()
@@ skipping 3356 matching lines @@
 }
 
 bool FrameView::canThrottleRendering() const
 {
     if (!RuntimeEnabledFeatures::renderingPipelineThrottlingEnabled())
         return false;
     return m_subtreeThrottled || (m_hiddenForThrottling && m_crossOriginForThrottling);
 }
 
 } // namespace blink