[es6] Perform the IsConstructor test in GetSuperConstructor.

src/interpreter/bytecode-generator.cc

Index: src/interpreter/bytecode-generator.cc
diff --git a/src/interpreter/bytecode-generator.cc b/src/interpreter/bytecode-generator.cc
index 9b31c13107e4a94c30c9f9ad4ee6ef9e64db9939..6d17bb559be20b7833035d3520e77d54818a61aa 100644
--- a/src/interpreter/bytecode-generator.cc
+++ b/src/interpreter/bytecode-generator.cc
@@ -2507,11 +2507,9 @@ void BytecodeGenerator::VisitCallSuper(Call* expr) {
   SuperCallReference* super = expr->expression()->AsSuperCallReference();
 
   // Prepare the constructor to the super call.
-  Register this_function = VisitForRegisterValue(super->this_function_var());
-  builder()->CallRuntime(Runtime::kInlineGetSuperConstructor, this_function);
-
-  Register constructor = this_function;  // Re-use dead this_function register.
-  builder()->StoreAccumulatorInRegister(constructor);
+  VisitForAccumulatorValue(super->this_function_var());
+  Register constructor = register_allocator()->NewRegister();
+  builder()->GetSuperConstructor(constructor);
 
   ZoneList<Expression*>* args = expr->arguments();