Add support for blue buttons.

ui/views/controls/button/button.h

Index: ui/views/controls/button/button.h
diff --git a/ui/views/controls/button/button.h b/ui/views/controls/button/button.h
index 8164be2a23836e4ba6c6fe36d1b772447796a32f..766ac24b444831b81ba5554aa27924f27ae888b9 100644
--- a/ui/views/controls/button/button.h
+++ b/ui/views/controls/button/button.h
@@ -39,11 +39,12 @@ class VIEWS_EXPORT Button : public View {
   };
 
   // Button styles with associated images and border painters.
-  // TODO(msw): Add "Blue Button", Checkbox, Radio, Menu, ComboBox, etc.
+  // TODO(msw): Add Checkbox, Radio, Menu, ComboBox, etc.
   enum ButtonStyle {
     STYLE_BUTTON = 0,
     STYLE_TEXTBUTTON,
     STYLE_NATIVE_TEXTBUTTON,
+    STYLE_BLUE_BUTTON,
     STYLE_COUNT,
   };