Enable under-invalidation checking in tests calling runAfterLayoutAndPaint()

third_party/WebKit/Source/platform/graphics/GraphicsLayer.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 580 matching lines @@
         return !it->value.trackedPaintInvalidations.isEmpty();
     return false;
 }
 
 void GraphicsLayer::trackPaintInvalidation(const DisplayItemClient& client, const IntRect& rect, PaintInvalidationReason reason)
 {
     if (!isTrackingOrCheckingPaintInvalidations() || rect.isEmpty())
         return;
 
     PaintInvalidationTracking& tracking = paintInvalidationTrackingMap().add(this, PaintInvalidationTracking()).storedValue->value;
-    PaintInvalidationInfo info = { &client, client.debugName(), rect, reason };
-    tracking.trackedPaintInvalidations.append(info);
+
+    if (m_isTrackingPaintInvalidations) {

[chrishtr, 2016/06/24 17:15:15]

Why is this conditional newly needed? Was it an oversight?

+        PaintInvalidationInfo info = { &client, client.debugName(), rect, reason };
+        tracking.trackedPaintInvalidations.append(info);
+    }
 
 #if DCHECK_IS_ON()
     if (RuntimeEnabledFeatures::slimmingPaintUnderInvalidationCheckingEnabled()) {
         // TODO(crbug.com/496260): Some antialiasing effects overflows the paint invalidation rect.
         IntRect r = rect;
         r.inflate(1);
         tracking.paintInvalidationRegionSinceLastPaint.unite(r);
     }
 #endif
 }
@@ skipping 758 matching lines @@
 {
     if (!layer) {
         fprintf(stderr, "Cannot showGraphicsLayerTree for (nil).\n");
         return;
     }
 
     String output = layer->layerTreeAsText(blink::LayerTreeIncludesDebugInfo);
     fprintf(stderr, "%s\n", output.utf8().data());
 }
 #endif