Skeleton typedef type implementation

lib/compiler/implementation/elements/elements.dart

Index: lib/compiler/implementation/elements/elements.dart
diff --git a/lib/compiler/implementation/elements/elements.dart b/lib/compiler/implementation/elements/elements.dart
index 8870678023f50765eec73cd5e53a196241a5571e..31536cde58e9e7e094262a869ad10fdd0e5cd2ea 100644
--- a/lib/compiler/implementation/elements/elements.dart
+++ b/lib/compiler/implementation/elements/elements.dart
@@ -491,21 +491,37 @@ class PrefixElement extends Element {
 }
 
 class TypedefElement extends Element implements TypeDeclarationElement {
-  Type cachedType;
   Typedef cachedNode;
+  TypedefType cachedType;
+  Type alias;
+
+  bool isResolved = false;
+  bool isBeingResolved = false;
 
   TypedefElement(SourceString name, Element enclosing)
       : super(name, ElementKind.TYPEDEF, enclosing);
 
-  Type computeType(Compiler compiler) {
+  /**
+   * Function signature for a typedef of a function type. The signature is
+   * kept to provide full information about parameter names through the mirror
+   * system.
+   *
+   * The [functionSignature] is not available until the typedef element has been
+   * resolved.
+   */
+  FunctionSignature functionSignature;
+
+  TypedefType computeType(Compiler compiler) {
     if (cachedType !== null) return cachedType;
-    cachedType = new FunctionType(null, null, this);
-    cachedType.initializeFrom(
-        compiler.computeFunctionType(this, compiler.resolveTypedef(this)));
+    Typedef node = parseNode(compiler);
+    Link<Type> parameters =
+        TypeDeclarationElement.createTypeVariables(this, node.typeParameters);
+    cachedType = new TypedefType(this, parameters);
+    compiler.resolveTypedef(this);
     return cachedType;
   }
 
-  Link<Type> get typeVariables() => const EmptyLink<Type>();
+  Link<Type> get typeVariables() => cachedType.typeArguments;
 
   Scope buildScope() =>
       new TypeDeclarationScope(enclosingElement.buildScope(), this);
@@ -658,7 +674,7 @@ class VariableListElement extends Element {
   VariableListElement cloneTo(Element enclosing, DiagnosticListener listener) {
     VariableListElement result;
     if (cachedNode !== null) {
-      result = new VariableListElement(cachedNode, kind, enclosing);
+      result = new VariableListElement.node(cachedNode, kind, enclosing);
     } else {
       result = new VariableListElement(kind, modifiers, enclosing);
     }
@@ -1489,7 +1505,7 @@ class TypeVariableElement extends Element {
 
   TypeVariableElement cloneTo(Element enclosing, DiagnosticListener listener) {
     TypeVariableElement result =
-        new TypeVariableElement(name, enclosing, node, type, bound);
+        new TypeVariableElement(name, enclosing, cachedNode, type, bound);
     return result;
   }
 }