Use static_cast in LinkNode<T>::value() so that it works with...

base/linked_list_unittest.cc

Index: base/linked_list_unittest.cc
===================================================================
--- base/linked_list_unittest.cc	(revision 28382)
+++ base/linked_list_unittest.cc	(working copy)
@@ -19,6 +19,18 @@
   int id_;
 };
 
+class MultipleInheritanceNodeBase {
+ public:
+  MultipleInheritanceNodeBase() : field_taking_up_space_(0) {}
+  int field_taking_up_space_;
+};
+
+class MultipleInheritanceNode : public MultipleInheritanceNodeBase,
+                                public LinkNode<MultipleInheritanceNode> {
+ public:
+  MultipleInheritanceNode() {}
+};
+
 // Checks that when iterating |list| (either from head to tail, or from
 // tail to head, as determined by |forward|), we get back |node_ids|,
 // which is an array of size |num_nodes|.
@@ -56,7 +68,6 @@
   ExpectListContents(list, 0, NULL);
 }
 
-
 TEST(LinkedList, Append) {
   LinkedList<Node> list;
   ExpectListContents(list, 0, NULL);
@@ -241,5 +252,10 @@
   }
 }
 
+TEST(LinkedList, MultipleInheritanceNode) {
+  MultipleInheritanceNode node;
+  EXPECT_EQ(&node, node.value());
+}
+
 }  // namespace
 }  // namespace base