Remove -webkit-appearance:default-button. This was only used in Safari.

Source/core/rendering/RenderTheme.cpp

Index: Source/core/rendering/RenderTheme.cpp
diff --git a/Source/core/rendering/RenderTheme.cpp b/Source/core/rendering/RenderTheme.cpp
index e9c8ea609398fb60dcb6e806cfebc145e4968b60..1e56442d2da704dbd9db07624697ba3d10f8e1f5 100644
--- a/Source/core/rendering/RenderTheme.cpp
+++ b/Source/core/rendering/RenderTheme.cpp
@@ -108,7 +108,6 @@ void RenderTheme::adjustStyle(StyleResolver* styleResolver, RenderStyle* style,
     case RadioPart:
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart: {
         // Border
         LengthBox borderBox(style->borderTopWidth(), style->borderRightWidth(), style->borderBottomWidth(), style->borderLeftWidth());
@@ -190,7 +189,6 @@ void RenderTheme::adjustStyle(StyleResolver* styleResolver, RenderStyle* style,
         return adjustRadioStyle(styleResolver, style, e);
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
         return adjustButtonStyle(styleResolver, style, e);
     case InnerSpinButtonPart:
@@ -269,7 +267,6 @@ bool RenderTheme::paint(RenderObject* o, const PaintInfo& paintInfo, const IntRe
     case RadioPart:
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
     case InnerSpinButtonPart:
         m_theme->paint(part, controlStatesForRenderer(o), const_cast<GraphicsContext*>(paintInfo.context), r, o->style()->effectiveZoom(), o->view()->frameView());
@@ -288,7 +285,6 @@ bool RenderTheme::paint(RenderObject* o, const PaintInfo& paintInfo, const IntRe
         return paintRadio(o, paintInfo, r);
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
         return paintButton(o, paintInfo, r);
     case InnerSpinButtonPart:
@@ -396,7 +392,6 @@ bool RenderTheme::paintBorderOnly(RenderObject* o, const PaintInfo& paintInfo, c
     case RadioPart:
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
     case MenulistPart:
     case MeterPart:
@@ -439,7 +434,6 @@ bool RenderTheme::paintDecorations(RenderObject* o, const PaintInfo& paintInfo,
     case RadioPart:
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
     case MenulistPart:
     case MeterPart:
@@ -630,7 +624,6 @@ bool RenderTheme::isControlStyled(const RenderStyle* style, const BorderData& bo
     switch (style->appearance()) {
     case PushButtonPart:
     case SquareButtonPart:
-    case DefaultButtonPart:
     case ButtonPart:
     case ProgressBarPart:
     case MeterPart:
@@ -707,8 +700,6 @@ ControlStates RenderTheme::controlStatesForRenderer(const RenderObject* o) const
         result |= CheckedState;
     if (isReadOnlyControl(o))
         result |= ReadOnlyState;
-    if (isDefault(o))
-        result |= DefaultState;
     if (!isActive(o))
         result |= WindowInactiveState;
     if (isIndeterminate(o))
@@ -822,11 +813,6 @@ bool RenderTheme::isSpinUpButtonPartHovered(const RenderObject* o) const
     return element->upDownState() == SpinButtonElement::Up;
 }
 
-bool RenderTheme::isDefault(const RenderObject* o) const
-{
-    return false;
-}
-
 #if !USE(NEW_THEME)
 
 void RenderTheme::adjustCheckboxStyle(StyleResolver*, RenderStyle* style, Element*) const