Add unittest to avoid duplicate id in gpu driver bug list

gpu/config/gpu_driver_bug_list_unittest.cc

 // Copyright (c) 2013 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 <stdint.h>
 
 #include <memory>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 189 matching lines @@
 
   bugs = list->MakeDecision(GpuControlList::kOsWin, "7.0", gpu_info);
   EXPECT_EQ(1u, bugs.count(DISABLE_D3D11));
 
   // test a higher driver version number
   gpu_info.driver_version = "9.18.13.2723";
   bugs = list->MakeDecision(GpuControlList::kOsWin, "7.0", gpu_info);
   EXPECT_EQ(0u, bugs.count(DISABLE_D3D11));
 }
 
+TEST_F(GpuDriverBugListTest, DuplicateBugIDCheck) {

[Zhenyao Mo, 2016/10/17 17:30:04]

nit: Duplicate -> Duplicated.

[qiankun, 2016/10/18 01:52:56]

Done.

+  std::unique_ptr<GpuDriverBugList> list(GpuDriverBugList::Create());
+  EXPECT_TRUE(list->LoadList(kGpuDriverBugListJson, GpuControlList::kAllOs));
+  EXPECT_FALSE(list->has_duplicate_entry_id());
+}
+
 }  // namespace gpu