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

Source/core/platform/ThemeTypes.h

Index: Source/core/platform/ThemeTypes.h
diff --git a/Source/core/platform/ThemeTypes.h b/Source/core/platform/ThemeTypes.h
index 8ef6b23754fe0b1a6347d5bc82c4772f118598e3..adc446948764e01db3da7a0badf29a4424b952b1 100644
--- a/Source/core/platform/ThemeTypes.h
+++ b/Source/core/platform/ThemeTypes.h
@@ -35,7 +35,6 @@ enum ControlState {
     EnabledState = 1 << 3,
     CheckedState = 1 << 4,
     ReadOnlyState = 1 << 5,
-    DefaultState = 1 << 6,
     WindowInactiveState = 1 << 7,
     IndeterminateState = 1 << 8,
     SpinUpState = 1 << 9, // Sub-state for HoverState and PressedState.
@@ -47,7 +46,7 @@ typedef unsigned ControlStates;
 // Must follow CSSValueKeywords.in order
 enum ControlPart {
     NoControlPart, CheckboxPart, RadioPart, PushButtonPart, SquareButtonPart, ButtonPart,
-    ButtonBevelPart, DefaultButtonPart, InnerSpinButtonPart, InputSpeechButtonPart, ListboxPart, ListItemPart,
+    ButtonBevelPart, InnerSpinButtonPart, InputSpeechButtonPart, ListboxPart, ListItemPart,
     MediaEnterFullscreenButtonPart, MediaExitFullscreenButtonPart, MediaFullScreenVolumeSliderPart, MediaFullScreenVolumeSliderThumbPart, MediaMuteButtonPart, MediaPlayButtonPart,
     MediaOverlayPlayButtonPart, MediaSeekBackButtonPart, MediaSeekForwardButtonPart, MediaRewindButtonPart, MediaReturnToRealtimeButtonPart, MediaToggleClosedCaptionsButtonPart,
     MediaSliderPart, MediaSliderThumbPart, MediaVolumeSliderContainerPart, MediaVolumeSliderPart, MediaVolumeSliderThumbPart,