Change DontCheck under-invalidation checking mode to CacheSkipper

Source/core/paint/BoxPainter.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/paint/BoxPainter.h"
 
 #include "core/HTMLNames.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
@@ skipping 60 matching lines @@
 
 bool bleedAvoidanceIsClipping(BackgroundBleedAvoidance bleedAvoidance)
 {
     return bleedAvoidance == BackgroundBleedClipOnly || bleedAvoidance == BackgroundBleedClipLayer;
 }
 
 } // anonymous namespace
 
 void BoxPainter::paintBoxDecorationBackgroundWithRect(const PaintInfo& paintInfo, const LayoutPoint& paintOffset, const LayoutRect& paintRect)
 {
+    const ComputedStyle& style = m_layoutBox.styleRef();
+
+    // FIXME: For now we don't have notification on media buffered range change from media player
+    // and miss paint invalidation on buffered range change. crbug.com/484288.
+    Optional<DisplayItemCacheSkipper> cacheSkipper;
+    if (style.appearance() == MediaSliderPart)
+        cacheSkipper.emplace(*paintInfo.context);
+
     LayoutObjectDrawingRecorder recorder(*paintInfo.context, m_layoutBox, DisplayItem::BoxDecorationBackground, boundsForDrawingRecorder(paintOffset));
     if (recorder.canUseCachedDrawing())
         return;
 
-    const ComputedStyle& style = m_layoutBox.styleRef();
     BoxDecorationData boxDecorationData(m_layoutBox);
 
-#if ENABLE(ASSERT)
-    // FIXME: For now we don't have notification on media buffered range change from media player
-    // and miss paint invalidation on buffered range change. crbug.com/484288.
-    if (style.appearance() == MediaSliderPart)
-        recorder.setUnderInvalidationCheckingMode(DrawingDisplayItem::DontCheck);
-#endif
-
     // FIXME: Should eventually give the theme control over whether the box shadow should paint, since controls could have
     // custom shadows of their own.
     if (!m_layoutBox.boxShadowShouldBeAppliedToBackground(boxDecorationData.bleedAvoidance))
         paintBoxShadow(paintInfo, paintRect, style, Normal);
 
     GraphicsContextStateSaver stateSaver(*paintInfo.context, false);
     if (bleedAvoidanceIsClipping(boxDecorationData.bleedAvoidance)) {
 
         stateSaver.save();
         FloatRoundedRect border = style.getRoundedBorderFor(paintRect);
@@ skipping 937 matching lines @@
                 else
                     clippedEdges |= GraphicsContext::BottomEdge;
             }
             // TODO: support non-integer shadows - crbug.com/334828
             context->drawInnerShadow(border, shadowColor, flooredIntSize(shadowOffset), shadowBlur, shadowSpread, clippedEdges);
         }
     }
 }
 
 } // namespace blink