Stop trying to use the italic version of the system font; it doesn't exist.

chrome/browser/ui/autofill/autofill_popup_controller_impl.cc

Index: chrome/browser/ui/autofill/autofill_popup_controller_impl.cc
diff --git a/chrome/browser/ui/autofill/autofill_popup_controller_impl.cc b/chrome/browser/ui/autofill/autofill_popup_controller_impl.cc
index 4bd8e38ab070773282c3d4120f04dc8f38e4899b..7e4acdf271bc89f60f094f363e169a16f8e759e8 100644
--- a/chrome/browser/ui/autofill/autofill_popup_controller_impl.cc
+++ b/chrome/browser/ui/autofill/autofill_popup_controller_impl.cc
@@ -113,8 +113,13 @@ AutofillPopupControllerImpl::AutofillPopupControllerImpl(
   ClearState();
 #if !defined(OS_ANDROID)
   subtext_font_ = name_font_.DeriveFont(kLabelFontSizeDelta);
+#if defined(OS_MACOSX)
+  // There is no italic version of the system font.
+  warning_font_ = name_font_;
+#else
   warning_font_ = name_font_.DeriveFont(0, gfx::Font::ITALIC);
 #endif
+#endif
 }
 
 AutofillPopupControllerImpl::~AutofillPopupControllerImpl() {}