Add typedef AST node boilerplate.

runtime/vm/kernel_binary.cc

Index: runtime/vm/kernel_binary.cc
diff --git a/runtime/vm/kernel_binary.cc b/runtime/vm/kernel_binary.cc
index e0a81d73ffbf3e43638ffcab268b012213e92933..d38dd8b0563f954f1dbb116d852022f294b82acc 100644
--- a/runtime/vm/kernel_binary.cc
+++ b/runtime/vm/kernel_binary.cc
@@ -215,6 +215,11 @@ Library* Library::ReadFrom(Reader* reader) {
   if (num_imports != 0) {
     FATAL("Deferred imports not implemented in VM");
   }
+  int num_typedefs = reader->ReadUInt();
+  typedefs().EnsureInitialized(num_typedefs);
+  for (intptr_t i = 0; i < num_typedefs; i++) {
+    typedefs().GetOrCreate<Typedef>(i, this)->ReadFrom(reader);
+  }
   int num_classes = reader->ReadUInt();
   classes().EnsureInitialized(num_classes);
   for (intptr_t i = 0; i < num_classes; i++) {
@@ -230,6 +235,20 @@ Library* Library::ReadFrom(Reader* reader) {
 }
 
 
+Typedef* Typedef::ReadFrom(Reader* reader) {
+  TRACE_READ_OFFSET();
+
+  canonical_name_ = reader->ReadCanonicalNameReference();
+  position_ = reader->ReadPosition(false);
+  name_ = Reference::ReadStringFrom(reader);
+  source_uri_index_ = reader->ReadUInt();
+  type_parameters_.ReadFrom(reader);
+  type_ = DartType::ReadFrom(reader);
+
+  return this;
+}
+
+
 Class* Class::ReadFrom(Reader* reader) {
   TRACE_READ_OFFSET();
 
@@ -313,6 +332,20 @@ CanonicalName* Reference::ReadClassFrom(Reader* reader, bool allow_null) {
 }
 
 
+CanonicalName* Reference::ReadTypedefFrom(Reader* reader) {
+  TRACE_READ_OFFSET();
+
+  CanonicalName* canonical_name = reader->ReadCanonicalNameReference();
+  if (canonical_name == NULL) {
+    FATAL("Expected a valid typedef reference, but got `null`");
+  }
+
+  canonical_name->set_referenced(true);
+
+  return canonical_name;
+}
+
+
 String* Reference::ReadStringFrom(Reader* reader) {
   int index = reader->ReadUInt();
   return reader->helper()->program()->string_table().strings()[index];
@@ -1411,6 +1444,8 @@ DartType* DartType::ReadFrom(Reader* reader) {
       return TypeParameterType::ReadFrom(reader);
     case kVectorType:
       return VectorType::ReadFrom(reader);
+    case kTypedefType:
+      return TypedefType::ReadFrom(reader);
     default:
       UNREACHABLE();
   }
@@ -1456,6 +1491,15 @@ InterfaceType* InterfaceType::ReadFrom(Reader* reader,
 }
 
 
+TypedefType* TypedefType::ReadFrom(Reader* reader) {
+  TRACE_READ_OFFSET();
+  CanonicalName* typedef_name = Reference::ReadTypedefFrom(reader);
+  TypedefType* type = new TypedefType(typedef_name);
+  type->type_arguments().ReadFromStatic<DartType>(reader);
+  return type;
+}
+
+
 FunctionType* FunctionType::ReadFrom(Reader* reader) {
   TRACE_READ_OFFSET();
   FunctionType* type = new FunctionType();