Remove strong mode support from rest argument creation.

src/mips64/interface-descriptors-mips64.cc

Index: src/mips64/interface-descriptors-mips64.cc
diff --git a/src/mips64/interface-descriptors-mips64.cc b/src/mips64/interface-descriptors-mips64.cc
index 7bbea92c958f54b7fb4d094b51879e6035745c14..c5c1311d94f32c0771410a71785fca205125031c 100644
--- a/src/mips64/interface-descriptors-mips64.cc
+++ b/src/mips64/interface-descriptors-mips64.cc
@@ -66,7 +66,6 @@ const Register ArgumentsAccessNewDescriptor::parameter_pointer() { return a3; }
 const Register RestParamAccessDescriptor::parameter_count() { return a2; }
 const Register RestParamAccessDescriptor::parameter_pointer() { return a3; }
 const Register RestParamAccessDescriptor::rest_parameter_index() { return a4; }
-const Register RestParamAccessDescriptor::language_mode() { return a1; }
 
 
 const Register ApiGetterDescriptor::function_address() { return a2; }