MenuButton: support Mac look & feel

ui/views/style/platform_style_mac.mm

Index: ui/views/style/platform_style_mac.mm
diff --git a/ui/views/style/platform_style_mac.mm b/ui/views/style/platform_style_mac.mm
index 550d9b2d957931d4e1929235b8d62c5f6bd57970..cb725c912bdb65b8fdd95a471a8a33e52b727b09 100644
--- a/ui/views/style/platform_style_mac.mm
+++ b/ui/views/style/platform_style_mac.mm
@@ -38,13 +38,32 @@ gfx::ImageSkia PlatformStyle::CreateComboboxArrow(bool is_enabled,
 }
 
 // static
+gfx::ImageSkia PlatformStyle::CreateMenuButtonArrow(bool is_enabled) {
+  const int kComboboxArrowWidth = 13;

[tapted, 2016/04/21 06:06:46]

kMenuButtonArrowWidth

[Elly Fong-Jones, 2016/04/21 15:30:27]

Done.

+  return gfx::CreateVectorIcon(gfx::VectorIconId::MENU_BUTTON_ARROW_MAC,
+                               kComboboxArrowWidth,
+                               is_enabled ? SK_ColorWHITE : SK_ColorBLACK);
+}
+
+// static
 std::unique_ptr<FocusableBorder> PlatformStyle::CreateComboboxBorder() {
   return base::WrapUnique(new FocusableRoundedBorder);
 }
 
 // static
 std::unique_ptr<Background> PlatformStyle::CreateComboboxBackground() {
-  return base::WrapUnique(new ComboboxBackgroundMac);
+  return base::WrapUnique(
+      new ComboboxBackgroundMac(GetComboboxArrowWidth(Combobox::STYLE_NORMAL)));

[tapted, 2016/04/21 06:06:46]

comment above about why STYLE_NORMAL is right here?

[Elly Fong-Jones, 2016/04/21 15:30:27]

It's only okay because of an implementation detail of Combobox. I put a comment
to that effect.

+}
+
+// static
+std::unique_ptr<FocusableBorder> PlatformStyle::CreateMenuButtonBorder() {
+  return base::WrapUnique(new FocusableRoundedBorder);
+}
+
+// static
+std::unique_ptr<Background> PlatformStyle::CreateMenuButtonBackground() {
+  return base::WrapUnique(new ComboboxBackgroundMac(GetMenuButtonArrowWidth()));
 }
 
 // static