Added code to associate a dart doc comment with a dart declaration node.

compiler/java/com/google/dart/compiler/ast/DartDeclaration.java

Index: compiler/java/com/google/dart/compiler/ast/DartDeclaration.java
===================================================================
--- compiler/java/com/google/dart/compiler/ast/DartDeclaration.java	(revision 2064)
+++ compiler/java/com/google/dart/compiler/ast/DartDeclaration.java	(working copy)
@@ -15,7 +15,8 @@
 public abstract class DartDeclaration<N extends DartExpression> extends DartNode {
 
   private N name; // Not visited.
-
+  private DartComment dartDoc;
+  
   protected DartDeclaration(N name) {
     this.name = becomeParentOf(name);
   }
@@ -30,4 +31,13 @@
 
   @Override
   public abstract Element getSymbol();
+  
+  public DartComment getDartDoc() {
+    return dartDoc;
+  }
+  
+  public void setDartDoc(DartComment dartDoc) {
+    // dartDoc is still parented by the containing DartUnit.
+    this.dartDoc = dartDoc;
+  }
 }