[es6] Fix invalid ToString in implementation of ToName.

src/full-codegen/mips/full-codegen-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS
 
 // Note on Mips implementation:
 //
 // The result_register() for mips is the 'v0' register, which is defined
 // by the ABI to contain function return values. However, the first
@@ skipping 3801 matching lines @@
 
   // Load the argument into v0 and convert it.
   VisitForAccumulatorValue(args->at(0));
 
   Label convert, done_convert;
   __ JumpIfSmi(v0, &convert);
   STATIC_ASSERT(FIRST_NAME_TYPE == FIRST_TYPE);
   __ GetObjectType(v0, a1, a1);
   __ Branch(&done_convert, le, a1, Operand(LAST_NAME_TYPE));
   __ bind(&convert);
-  ToStringStub stub(isolate());
-  __ mov(a0, v0);
-  __ CallStub(&stub);
+  __ Push(v0);
+  __ CallRuntime(Runtime::kToName, 1);
   __ bind(&done_convert);
   context()->Plug(v0);
 }
 
 
 void FullCodeGenerator::EmitToObject(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK_EQ(1, args->length());
 
   // Load the argument into a0 and convert it.
@@ skipping 1389 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS