Have Chrome draw top window border when using custom titlebar.

chrome/browser/themes/theme_service_win.h

Index: chrome/browser/themes/theme_service_win.h
diff --git a/chrome/browser/themes/theme_service_win.h b/chrome/browser/themes/theme_service_win.h
index a702f389417d92a2460c44840da4fafeffb4291b..770bea523d2ae266e5c64cc4d78f344c03eceba5 100644
--- a/chrome/browser/themes/theme_service_win.h
+++ b/chrome/browser/themes/theme_service_win.h
@@ -33,6 +33,9 @@ class ThemeServiceWin : public ThemeService {
   // The DWM frame color, if available; white otherwise.
   SkColor dwm_frame_color_;
 
+  // The DWM accent border color, if available; white otherwise.
+  SkColor dwm_accent_border_color_;
+
   DISALLOW_COPY_AND_ASSIGN(ThemeServiceWin);
 };