Replace intptr_t with TokenDescriptor

runtime/lib/errors.cc

Index: runtime/lib/errors.cc
diff --git a/runtime/lib/errors.cc b/runtime/lib/errors.cc
index 434143b30e3de86ec39258dcad8448464867184f..dd7acd86c766b070cbe19073250c2e59b1d41213 100644
--- a/runtime/lib/errors.cc
+++ b/runtime/lib/errors.cc
@@ -23,10 +23,10 @@ DEFINE_NATIVE_ENTRY(AssertionError_throwNew, 2) {
 
   // No need to type check the arguments. This function can only be called
   // internally from the VM.
-  intptr_t assertion_start =
-      Smi::CheckedHandle(arguments->NativeArgAt(0)).Value();
-  intptr_t assertion_end =
-      Smi::CheckedHandle(arguments->NativeArgAt(1)).Value();
+  const TokenPosition assertion_start =
+      TokenPosition(Smi::CheckedHandle(arguments->NativeArgAt(0)).Value());
+  const TokenPosition assertion_end =
+      TokenPosition(Smi::CheckedHandle(arguments->NativeArgAt(1)).Value());
 
   const Array& args = Array::Handle(Array::New(4));
 
@@ -66,7 +66,8 @@ DEFINE_NATIVE_ENTRY(AssertionError_throwNew, 2) {
 DEFINE_NATIVE_ENTRY(TypeError_throwNew, 5) {
   // No need to type check the arguments. This function can only be called
   // internally from the VM.
-  intptr_t location = Smi::CheckedHandle(arguments->NativeArgAt(0)).Value();
+  const TokenPosition location =
+      TokenPosition(Smi::CheckedHandle(arguments->NativeArgAt(0)).Value());
   const Instance& src_value =
       Instance::CheckedHandle(arguments->NativeArgAt(1));
   const String& dst_type_name =
@@ -87,7 +88,7 @@ DEFINE_NATIVE_ENTRY(TypeError_throwNew, 5) {
 // Return value: none, throws an exception.
 DEFINE_NATIVE_ENTRY(FallThroughError_throwNew, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(Smi, smi_pos, arguments->NativeArgAt(0));
-  intptr_t fallthrough_pos = smi_pos.Value();
+  TokenPosition fallthrough_pos = TokenPosition(smi_pos.Value());
 
   const Array& args = Array::Handle(Array::New(2));
 
@@ -113,7 +114,7 @@ DEFINE_NATIVE_ENTRY(FallThroughError_throwNew, 1) {
 DEFINE_NATIVE_ENTRY(AbstractClassInstantiationError_throwNew, 2) {
   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();
+  TokenPosition error_pos = TokenPosition(smi_pos.Value());
 
   const Array& args = Array::Handle(Array::New(3));