Fix a race in WorkerThreadTicker test.

chrome/common/worker_thread_ticker_unittest.cc

 // Copyright (c) 2009 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 "chrome/common/worker_thread_ticker.h"
 
 #include "base/message_loop.h"
 #include "base/platform_thread.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 29 matching lines @@
   MessageLoop::current()->PostDelayedTask(FROM_HERE,
                                           new MessageLoop::QuitTask(), 500);
   MessageLoop::current()->Run();
 }
 
 }  // namespace
 
 TEST(WorkerThreadTickerTest, Basic) {
   MessageLoop loop;
 
+  TestCallback callback;
   WorkerThreadTicker ticker(50);
-  TestCallback callback;
   EXPECT_FALSE(ticker.IsRunning());
   EXPECT_TRUE(ticker.RegisterTickHandler(&callback));
   EXPECT_TRUE(ticker.UnregisterTickHandler(&callback));
   EXPECT_TRUE(ticker.Start());
   EXPECT_FALSE(ticker.RegisterTickHandler(&callback));
   EXPECT_FALSE(ticker.UnregisterTickHandler(&callback));
   EXPECT_TRUE(ticker.IsRunning());
   EXPECT_FALSE(ticker.Start());  // Can't start when it is running.
   EXPECT_TRUE(ticker.Stop());
   EXPECT_FALSE(ticker.IsRunning());
   EXPECT_FALSE(ticker.Stop());  // Can't stop when it isn't running.
 }
 
 TEST(WorkerThreadTickerTest, Callback) {
   MessageLoop loop;
 
+  TestCallback callback;
   WorkerThreadTicker ticker(50);
-  TestCallback callback;
   ASSERT_TRUE(ticker.RegisterTickHandler(&callback));
 
   ASSERT_TRUE(ticker.Start());
   RunMessageLoopForAWhile();
   EXPECT_TRUE(callback.counter() > 0);
 
   ASSERT_TRUE(ticker.Stop());
   const int counter_value = callback.counter();
   RunMessageLoopForAWhile();
   EXPECT_EQ(counter_value, callback.counter());
@@ skipping 12 matching lines @@
     EXPECT_TRUE(callback.counter() > 0);
   }
   const int counter_value = callback.counter();
   RunMessageLoopForAWhile();
   EXPECT_EQ(counter_value, callback.counter());
 }
 
 TEST(WorkerThreadTickerTest, LongCallback) {
   MessageLoop loop;
 
+  LongCallback callback;
   WorkerThreadTicker ticker(50);
-  LongCallback callback;
   ASSERT_TRUE(ticker.RegisterTickHandler(&callback));
 
   ASSERT_TRUE(ticker.Start());
   RunMessageLoopForAWhile();
 }