ToNumber(Symbol) should throw TypeError

src/messages.js

Index: src/messages.js
diff --git a/src/messages.js b/src/messages.js
index 90a756cee1abc64cdd09c492bde4777f4497d3d0..eba1e16ece04e8603ff1ca67a5e9ab8ddcaec061 100644
--- a/src/messages.js
+++ b/src/messages.js
@@ -164,6 +164,7 @@ var kMessages = {
   harmony_const_assign:          ["Assignment to constant variable."],
   symbol_to_string:              ["Cannot convert a Symbol value to a string"],
   symbol_to_primitive:           ["Cannot convert a Symbol wrapper object to a primitive value"],
+  symbol_to_number:              ["Cannot convert a Symbol value to a number"],
   invalid_module_path:           ["Module does not export '", "%0", "', or export is not itself a module"],
   module_type_error:             ["Module '", "%0", "' used improperly"],
   module_export_undefined:       ["Export '", "%0", "' is not defined in module"]