Use the NativeTheme to create the text color for text during the generated card animation.

chrome/browser/ui/autofill/autofill_dialog_types.h

Index: chrome/browser/ui/autofill/autofill_dialog_types.h
diff --git a/chrome/browser/ui/autofill/autofill_dialog_types.h b/chrome/browser/ui/autofill/autofill_dialog_types.h
index 9c96b8bb97347df4c4482a3ccde74dc1b62e8dd2..c661f709160ff7e3117ab490850150b128c93574 100644
--- a/chrome/browser/ui/autofill/autofill_dialog_types.h
+++ b/chrome/browser/ui/autofill/autofill_dialog_types.h
@@ -171,9 +171,6 @@ struct DialogOverlayString {
   // Text content of the message.
   base::string16 text;
 
-  // Color of the message's text.
-  SkColor text_color;
-
   // Font to render the message's text in.
   gfx::Font font;
 };