views: support disabled color for CTA buttons

ui/native_theme/native_theme_dark_aura.cc

Index: ui/native_theme/native_theme_dark_aura.cc
diff --git a/ui/native_theme/native_theme_dark_aura.cc b/ui/native_theme/native_theme_dark_aura.cc
index 443d955642302b7fb153e96ea8dacf7195cd9f92..3280d4d91700b9cce1abe9a5f2a38d9c0e204980 100644
--- a/ui/native_theme/native_theme_dark_aura.cc
+++ b/ui/native_theme/native_theme_dark_aura.cc
@@ -42,6 +42,8 @@ SkColor NativeThemeDarkAura::GetSystemColor(ColorId color_id) const {
       return kButtonEnabledColor;
     case kColorId_CallToActionColor:
       return gfx::kGoogleBlue300;
+    case kColorId_CallToActionDisabledColor:
+      return SkColorSetA(gfx::kGoogleBlue300, 255.0 * 0.38);

[Evan Stade, 2016/09/07 16:00:35]

I think it makes sense to keep this in MdTextButton unless we're going to use it
somewhere else. Since presumably all native themes want the disabled CTA color
to be enabled with 0.38a (normally we use hex, so 0x61), it's simpler to avoid
adding a new color id and copying the constant in a lot of places, and instead
just stick a hard-coded alpha in MdTextButton.

[Elly Fong-Jones, 2016/09/07 16:59:59]

Done.

 
     // Label
     case kColorId_LabelEnabledColor: