Fix a race in MultiThreadedProxyResolverTest.ThreeThreads_Basic.

net/proxy/multi_threaded_proxy_resolver_unittest.cc

 // Copyright (c) 2012 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 "net/proxy/multi_threaded_proxy_resolver.h"
 
 #include <vector>
 
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ skipping 537 matching lines @@
 
   base::MessageLoop::current()->RunUntilIdle();
 
   // We now block the first resolver to ensure a request is sent to the second
   // thread.
   factory().resolvers()[0]->Block();
   rv = resolver().GetProxyForURL(GURL("http://request1"), &results[1],
                                  callback[1].callback(), &request[1],
                                  BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
+  factory().resolvers()[0]->WaitUntilBlocked();
   rv = resolver().GetProxyForURL(GURL("http://request2"), &results[2],
                                  callback[2].callback(), &request[2],
                                  BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
   EXPECT_EQ(0, callback[2].WaitForResult());
   ASSERT_EQ(2u, factory().resolvers().size());
 
   // We now block the second resolver as well to ensure a request is sent to the
   // third thread.
   factory().resolvers()[1]->Block();
   rv = resolver().GetProxyForURL(GURL("http://request3"), &results[3],
                                  callback[3].callback(), &request[3],
                                  BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
+  factory().resolvers()[1]->WaitUntilBlocked();
   rv = resolver().GetProxyForURL(GURL("http://request4"), &results[4],
                                  callback[4].callback(), &request[4],
                                  BoundNetLog());
   EXPECT_EQ(ERR_IO_PENDING, rv);
   EXPECT_EQ(0, callback[4].WaitForResult());
 
   // We should now have a total of 3 threads, each with its own ProxyResolver
   // that will get initialized with the same data.
   ASSERT_EQ(3u, factory().resolvers().size());
 
@@ skipping 196 matching lines @@
   }
   // The factory destructor will block until the worker thread stops, but it may
   // post tasks to the origin message loop which are still pending. Run them
   // now to ensure it works as expected.
   base::RunLoop().RunUntilIdle();
 }
 
 }  // namespace
 
 }  // namespace net