Rename GET_NATIVE_ARGUMENT macro to GET_NON_NULL_NATIVE_ARGUMENT.

runtime/lib/error.cc

Index: runtime/lib/error.cc
===================================================================
--- runtime/lib/error.cc	(revision 15918)
+++ runtime/lib/error.cc	(working copy)
@@ -82,7 +82,7 @@
 // Arg0: index of the case clause token into which we fall through.
 // Return value: none, throws an exception.
 DEFINE_NATIVE_ENTRY(FallThroughError_throwNew, 1) {
-  GET_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
   intptr_t fallthrough_pos = smi_pos.Value();
 
   // Allocate a new instance of type FallThroughError.
@@ -114,8 +114,8 @@
 // Arg1: class name of the abstract class that cannot be instantiated.
 // Return value: none, throws an exception.
 DEFINE_NATIVE_ENTRY(AbstractClassInstantiationError_throwNew, 2) {
-  GET_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
-  GET_NATIVE_ARGUMENT(String, class_name, arguments->NativeArgAt(1));
+  GET_NON_NULL_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(String, class_name, arguments->NativeArgAt(1));
   intptr_t error_pos = smi_pos.Value();
 
   // Allocate a new instance of type AbstractClassInstantiationError.
@@ -146,8 +146,9 @@
 // Arg1: name of the method that was not resolved at compile time.
 // Return value: none, throws an exception.
 DEFINE_NATIVE_ENTRY(NoSuchMethodError_throwNew, 2) {
-  GET_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
-  GET_NATIVE_ARGUMENT(String, function_name, arguments->NativeArgAt(1));
+  GET_NON_NULL_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
+  GET_NON_NULL_NATIVE_ARGUMENT(
+      String, function_name, arguments->NativeArgAt(1));
   intptr_t call_pos = smi_pos.Value();
   // Allocate a new instance of type NoSuchMethodError.
   const Instance& error = Instance::Handle(