Use windows keycodes under linux (and all non-windows platforms).

views/widget/widget_gtk.cc

Index: views/widget/widget_gtk.cc
===================================================================
--- views/widget/widget_gtk.cc	(revision 27238)
+++ views/widget/widget_gtk.cc	(working copy)
@@ -700,12 +700,12 @@
 }
 
 gboolean WidgetGtk::OnKeyPress(GtkWidget* widget, GdkEventKey* event) {
-  KeyEvent key_event(event, false);
+  KeyEvent key_event(event);
   return root_view_->ProcessKeyEvent(key_event);
 }
 
 gboolean WidgetGtk::OnKeyRelease(GtkWidget* widget, GdkEventKey* event) {
-  KeyEvent key_event(event, false);
+  KeyEvent key_event(event);
   return root_view_->ProcessKeyEvent(key_event);
 }