Make <meter> transparent if -webkit-appearance:none or background CSS property is specified.

third_party/WebKit/Source/core/html/shadow/MeterShadowElement.cpp

 /*
  * Copyright (C) 2011 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 24 matching lines @@
 #include "core/CSSPropertyNames.h"
 #include "core/HTMLNames.h"
 #include "core/html/HTMLMeterElement.h"
 #include "core/layout/LayoutMeter.h"
 #include "core/layout/LayoutTheme.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
+inline MeterFallbackElement::MeterFallbackElement(Document& document)
+    : HTMLDivElement(document)
+{
+    setHasCustomStyleCallbacks();
+}
+
+DEFINE_NODE_FACTORY(MeterFallbackElement)
+
+PassRefPtr<ComputedStyle> MeterFallbackElement::customStyleForLayoutObject()
+{
+    Element* host = shadowHost();
+    RefPtr<ComputedStyle> style = originalStyleForLayoutObject();
+    if (!host || !host->computedStyle() || host->computedStyle()->appearance() != MeterPart)
+        return style.release;
+    RefPtr<ComputedStyle> newStyle = ComputedStyle::clone(*style);
+    newStyle->setDisplay(NONE);
+    return newStyle.release();
+}
+
 inline MeterShadowElement::MeterShadowElement(Document& document)
     : HTMLDivElement(document)
 {
 }
 
 HTMLMeterElement* MeterShadowElement::meterElement() const
 {
     return toHTMLMeterElement(shadowHost());
 }
 
 bool MeterShadowElement::layoutObjectIsNeeded(const ComputedStyle& style)
 {
     LayoutObject* layoutObject = meterElement()->layoutObject();
     return layoutObject && !LayoutTheme::theme().supportsMeter(layoutObject->style()->appearance()) && HTMLDivElement::layoutObjectIsNeeded(style);
 }
 
 inline MeterInnerElement::MeterInnerElement(Document& document)
     : MeterShadowElement(document)
 {
+    setHasCustomStyleCallbacks();
 }
 
 PassRefPtrWillBeRawPtr<MeterInnerElement> MeterInnerElement::create(Document& document)
 {
     RefPtrWillBeRawPtr<MeterInnerElement> element = adoptRefWillBeNoop(new MeterInnerElement(document));
     element->setShadowPseudoId(AtomicString("-webkit-meter-inner-element", AtomicString::ConstructFromLiteral));
     return element.release();
 }
 
 bool MeterInnerElement::layoutObjectIsNeeded(const ComputedStyle& style)
 {
     if (meterElement()->openShadowRoot())
         return HTMLDivElement::layoutObjectIsNeeded(style);
 
     LayoutObject* layoutObject = meterElement()->layoutObject();
     return layoutObject && !LayoutTheme::theme().supportsMeter(layoutObject->style()->appearance()) && HTMLDivElement::layoutObjectIsNeeded(style);
 }
 
 LayoutObject* MeterInnerElement::createLayoutObject(const ComputedStyle&)
 {
     return new LayoutMeter(this);
 }
 
+PassRefPtr<ComputedStyle> MeterInnerElement::customStyleForLayoutObject()
+{
+    Element* host = shadowHost();
+    RefPtr<ComputedStyle> style = originalStyleForLayoutObject();
+    if (!host || !host->computedStyle() || host->computedStyle()->appearance() == MeterPart)
+        return style.release;
+    RefPtr<ComputedStyle> newStyle = ComputedStyle::clone(*style);
+    newStyle->setDisplay(NONE);
+    return newStyle.release();
+}
+
 inline MeterBarElement::MeterBarElement(Document& document)
     : MeterShadowElement(document)
 {
 }
 
 PassRefPtrWillBeRawPtr<MeterBarElement> MeterBarElement::create(Document& document)
 {
     RefPtrWillBeRawPtr<MeterBarElement> element = adoptRefWillBeNoop(new MeterBarElement(document));
     element->setShadowPseudoId(AtomicString("-webkit-meter-bar", AtomicString::ConstructFromLiteral));
     return element.release();
@@ skipping 33 matching lines @@
         return optimumPseudoId;
     }
 }
 
 void MeterValueElement::setWidthPercentage(double width)
 {
     setInlineStyleProperty(CSSPropertyWidth, width, CSSPrimitiveValue::UnitType::Percentage);
 }
 
 }