Add typedef AST node boilerplate.

pkg/kernel/lib/text/ast_to_text.dart

Index: pkg/kernel/lib/text/ast_to_text.dart
diff --git a/pkg/kernel/lib/text/ast_to_text.dart b/pkg/kernel/lib/text/ast_to_text.dart
index 03f7fa6382646163e47475975ef80690ae46503e..198c21462d0cd9b6da7859e38e559d4603721602 100644
--- a/pkg/kernel/lib/text/ast_to_text.dart
+++ b/pkg/kernel/lib/text/ast_to_text.dart
@@ -210,6 +210,12 @@ class Printer extends Visitor<Null> {
     return '$library::$name';
   }
 
+  String getTypedefReference(Typedef node) {
+    if (node == null) return '<No Typedef>';
+    String library = getLibraryReference(node.enclosingLibrary);
+    return '$library::${node.name}';
+  }
+
   static final String emptyNameString = '•';
   static final Name emptyName = new Name(emptyNameString);
 
@@ -281,6 +287,7 @@ class Printer extends Visitor<Null> {
     }
     endLine();
     var inner = new Printer._inner(this, imports);
+    library.typedefs.forEach(inner.writeNode);
     library.classes.forEach(inner.writeNode);
     library.fields.forEach(inner.writeNode);
     library.procedures.forEach(inner.writeNode);
@@ -313,6 +320,7 @@ class Printer extends Visitor<Null> {
       writeWord(prefix);
       endLine(' {');
       ++inner.indentation;
+      library.typedefs.forEach(inner.writeNode);
       library.classes.forEach(inner.writeNode);
       library.fields.forEach(inner.writeNode);
       library.procedures.forEach(inner.writeNode);
@@ -429,6 +437,15 @@ class Printer extends Visitor<Null> {
     writeWord('Vector');
   }
 
+  visitTypedefType(TypedefType type) {
+    writeTypedefReference(type.typedefNode);
+    if (type.typeArguments.isNotEmpty) {
+      writeSymbol('<');
+      writeList(type.typeArguments, writeType);
+      writeSymbol('>');
+    }
+  }
+
   void writeModifier(bool isThere, String name) {
     if (isThere) {
       writeWord(name);
@@ -610,6 +627,10 @@ class Printer extends Visitor<Null> {
     writeWord(getClassReference(classNode));
   }
 
+  void writeTypedefReference(Typedef typedefNode) {
+    writeWord(getTypedefReference(typedefNode));
+  }
+
   void writeLibraryReference(Library library) {
     writeWord(getLibraryReference(library));
   }
@@ -751,6 +772,16 @@ class Printer extends Visitor<Null> {
     endLine('}');
   }
 
+  visitTypedef(Typedef node) {
+    writeIndentation();
+    writeWord('typedef');
+    writeWord(node.name);
+    writeTypeParameterList(node.typeParameters);
+    writeSpaced('=');
+    writeNode(node.type);
+    endLine(';');
+  }
+
   visitInvalidExpression(InvalidExpression node) {
     writeWord('invalid-expression');
   }