Fix some egregious bugs in Var.

ppapi/tests/test_var.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ppapi/tests/test_var.h"
 
 #include <string.h>
 
 #include <limits>
 
@@ skipping 46 matching lines @@
     ASSERT_EQ(kStrLen, len);
     ASSERT_EQ(0, strncmp(kStr, result, kStrLen));
 
     // Destroy the string, readback should now fail.
     var_interface_->Release(str);
     result = var_interface_->VarToUtf8(str, &len);
     ASSERT_EQ(0, len);
     ASSERT_EQ(NULL, result);
   }
 
+  // Make sure we can assign a C++ object to itself and it stays alive.
+  {
+    pp::Var a("test");
+    a = a;
+    ASSERT_TRUE(a.AsString() == "test");
+  }
+
   // Make sure nothing leaked.
   ASSERT_TRUE(testing_interface_->GetLiveObjectsForInstance(
       instance_->pp_instance()) == before_object);
 
   PASS();
 }
 
 std::string TestVar::TestInvalidAndEmpty() {
   PP_Var invalid_string;
   invalid_string.type = PP_VARTYPE_STRING;
@@ skipping 161 matching lines @@
   if (length != 0) {
     return "Expected 0 on string conversion from Double var.";
   }
   if (result != NULL) {
     return "Expected NULL on string conversion from Double var.";
   }
 
   PASS();
 }