Add a reference table implementation.

This is suitable for pinned array references and the like.

I've also brought in some of the human-readable type printing stuff
for the benefit of the reference table dumping code.

This patch includes tests, but doesn't yet wire anything up.

Change-Id: Iaf6066201bbd254e033dee4fd0b8dfd0bc17afa9
diff --git a/src/reference_table_test.cc b/src/reference_table_test.cc
new file mode 100644
index 0000000..c61e3c9
--- /dev/null
+++ b/src/reference_table_test.cc
@@ -0,0 +1,38 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+
+#include "common_test.h"
+
+#include "reference_table.h"
+
+#include "gtest/gtest.h"
+
+namespace art {
+
+class ReferenceTableTest : public RuntimeTest {
+};
+
+TEST_F(ReferenceTableTest, Basics) {
+  Object* o1 = String::AllocFromModifiedUtf8(0, "hello");
+  Object* o2 = ShortArray::Alloc(0);
+
+  // TODO: rewrite Dump to take a std::ostream& so we can test it better.
+
+  ReferenceTable rt("test", 0, 4);
+  rt.Dump();
+  EXPECT_EQ(0U, rt.Size());
+  rt.Remove(NULL);
+  EXPECT_EQ(0U, rt.Size());
+  rt.Remove(o1);
+  EXPECT_EQ(0U, rt.Size());
+  rt.Add(o1);
+  EXPECT_EQ(1U, rt.Size());
+  rt.Add(o2);
+  EXPECT_EQ(2U, rt.Size());
+  rt.Dump();
+  rt.Remove(o1);
+  EXPECT_EQ(1U, rt.Size());
+  rt.Remove(o2);
+  EXPECT_EQ(0U, rt.Size());
+}
+
+}  // namespace art