Make html lists print a nice toString method.

tools/dom/templates/html/impl/impl_Element.darttemplate

Index: tools/dom/templates/html/impl/impl_Element.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_Element.darttemplate b/tools/dom/templates/html/impl/impl_Element.darttemplate
index 6d34148c72457c2b0e0d4ecf50f8053071d8dbe3..4993f03c6f472e7cd0c181ea58f37a5e8e00fe80 100644
--- a/tools/dom/templates/html/impl/impl_Element.darttemplate
+++ b/tools/dom/templates/html/impl/impl_Element.darttemplate
@@ -282,6 +282,13 @@ class _ChildrenElementList implements List {
   Map<int, Element> asMap() {
     return IterableMixinWorkaround.asMapList(this);
   }
+
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
 }
 
 // TODO(jacobr): this is an inefficient implementation but it is hard to see
@@ -492,6 +499,13 @@ class _FrozenElementList implements List {
   Map<int, Element> asMap() {
     return IterableMixinWorkaround.asMapList(this);
   }
+
+  String toString() {
+    StringBuffer buffer = new StringBuffer('[');
+    buffer.writeAll(this, ', ');
+    buffer.write(']');
+    return buffer.toString();
+  }
 }
 
 class _FrozenElementListIterator implements Iterator<Element> {
@@ -979,6 +993,12 @@ $if DART2JS
 $else
 $endif
 
+  /** 
+   * Print out a String representation of this Element. By default, this is
+   * this Element's tagName.
+   */
+  String toString() => this.tagName;
+
 $!MEMBERS
 }