[turbofan] Implement the call protocol properly for direct calls.

src/ia32/macro-assembler-ia32.h

Index: src/ia32/macro-assembler-ia32.h
diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index 0681c5f6babdab0ef66488a138f81d3d7b93cc46..bff3c041a4f130dcf5630ba316b8dc0fbf6a0ff3 100644
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -22,6 +22,7 @@ const Register kInterpreterAccumulatorRegister = {Register::kCode_eax};
 const Register kInterpreterRegisterFileRegister = {Register::kCode_edx};
 const Register kInterpreterBytecodeOffsetRegister = {Register::kCode_ecx};
 const Register kInterpreterBytecodeArrayRegister = {Register::kCode_edi};
+const Register kJavaScriptCallArgCountRegister = {Register::kCode_eax};
 const Register kRuntimeCallFunctionRegister = {Register::kCode_ebx};
 const Register kRuntimeCallArgCountRegister = {Register::kCode_eax};