Add TypedData instance kinds.

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index 8027aaf3c7ceb46e7b2ecfb99ce3f3682a702934..454518e2062d0a1e03aea0474fb2465761d5a8d0 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -6797,6 +6797,15 @@ class TypedData : public Instance {
     return ElementSizeInBytes(cid);
   }
 
+  const char* ElementTypeName() const {
+    switch (ElementType()) {
+#define V(name) case k##name##Element: return #name;
+CLASS_LIST_TYPED_DATA(V)
+#undef V
+    }
+    UNREACHABLE();
+    return "UnknownTypedDataElementType";
+  }
 
   TypedDataElementType ElementType() const {
     intptr_t cid = raw()->GetClassId();
@@ -6973,6 +6982,16 @@ class ExternalTypedData : public Instance {
     return ElementSizeInBytes(cid);
   }
 
+  const char* ElementTypeName() const {
+    switch (ElementType()) {
+#define V(name) case k##name##Element: return #name;
+CLASS_LIST_TYPED_DATA(V)
+#undef V
+    }
+    UNREACHABLE();
+    return "UnknownTypedDataElementType";
+  }
+
   TypedDataElementType ElementType() const {
     intptr_t cid = raw()->GetClassId();
     return ElementType(cid);