Disable the input method and unicode sub menus in context menus.

BUG=http://crosbug.com/2458
TEST=Right click in an input box.

Review URL: http://codereview.chromium.org/2855024
diff --git a/resources/gtkrc b/resources/gtkrc
index 4d6c501..accb5ce 100644
--- a/resources/gtkrc
+++ b/resources/gtkrc
@@ -8,6 +8,12 @@
 # Diable mnemonics for labels and menu items.
 gtk-enable-mnemonics = 0
 
+# Disable the "Input Methods" sub menu in context menus.
+gtk-show-input-method-menu = 0
+
+# Disable the "Insert Unicode Control Character" sub menu in context menus.
+gtk-show-unicode-menu = 0
+
 style "default" {
   fg[NORMAL]        = @fg_color
   fg[PRELIGHT]      = @text_color