Fix for ::selection pseudo element to work on input elements

Source/core/rendering/RenderObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1771 matching lines @@
 bool RenderObject::isSelectable() const
 {
     return !isInert() && !(style()->userSelect() == SELECT_NONE && style()->userModify() == READ_ONLY);
 }
 
 Color RenderObject::selectionBackgroundColor() const
 {
     if (!isSelectable())
         return Color::transparent;
 
-    if (RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyle(PseudoStyleRequest(SELECTION)))
+    if (RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyleFromParentOrShadowHost())
         return resolveColor(pseudoStyle.get(), CSSPropertyBackgroundColor).blendWithWhite();
     return frame()->selection().isFocusedAndActive() ?
         RenderTheme::theme().activeSelectionBackgroundColor() :
         RenderTheme::theme().inactiveSelectionBackgroundColor();
 }
 
 Color RenderObject::selectionColor(int colorProperty) const
 {
     // If the element is unselectable, or we are only painting the selection,
     // don't override the foreground color with the selection foreground color.
     if (!isSelectable() || (frame()->view()->paintBehavior() & PaintBehaviorSelectionOnly))
         return resolveColor(colorProperty);
 
-    if (RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyle(PseudoStyleRequest(SELECTION)))
+    if (RefPtr<RenderStyle> pseudoStyle = getUncachedPseudoStyleFromParentOrShadowHost())
         return resolveColor(pseudoStyle.get(), colorProperty);
     if (!RenderTheme::theme().supportsSelectionForegroundColors())
         return resolveColor(colorProperty);
     return frame()->selection().isFocusedAndActive() ?
         RenderTheme::theme().activeSelectionForegroundColor() :
         RenderTheme::theme().inactiveSelectionForegroundColor();
 }
 
 Color RenderObject::selectionForegroundColor() const
 {
@@ skipping 1148 matching lines @@
 
     if (pseudoStyleRequest.pseudoId == FIRST_LINE_INHERITED) {
         RefPtr<RenderStyle> result = document().ensureStyleResolver().styleForElement(element, parentStyle, DisallowStyleSharing);
         result->setStyleType(FIRST_LINE_INHERITED);
         return result.release();
     }
 
     return document().ensureStyleResolver().pseudoStyleForElement(element, pseudoStyleRequest, parentStyle);
 }
 
+PassRefPtr<RenderStyle> RenderObject::getUncachedPseudoStyleFromParentOrShadowHost() const
+{
+    if (!node())
+        return nullptr;
+
+    if (Element* shadowHost = node()->shadowHost()) {
+        if (shadowHost->isFormControlElement())
+            return shadowHost->renderer()->getUncachedPseudoStyle(PseudoStyleRequest(SELECTION));
+    }
+
+    return getUncachedPseudoStyle(PseudoStyleRequest(SELECTION));
+}
+
 bool RenderObject::hasBlendMode() const
 {
     return RuntimeEnabledFeatures::cssCompositingEnabled() && style() && style()->hasBlendMode();
 }
 
 static Color decorationColor(const RenderObject* object, RenderStyle* style)
 {
     // Check for text decoration color first.
     StyleColor result = style->visitedDependentDecorationColor();
     if (!result.isCurrentColor())
@@ skipping 375 matching lines @@
 {
     if (object1) {
         const WebCore::RenderObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif