Use ScopedTaskEnvironment instead of MessageLoop in service_manager::test::ServiceTest.

content/browser/dom_storage/local_storage_context_mojo_unittest.cc

 // Copyright 2016 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 "content/browser/dom_storage/local_storage_context_mojo.h"
 
 #include "base/files/file_enumerator.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 659 matching lines @@
   }
 
   void TearDown() override {
     ServiceTest::TearDown();
   }
 
   std::unique_ptr<service_manager::Service> CreateService() override {
     return base::MakeUnique<ServiceTestClient>(this);
   }
 
-  std::unique_ptr<base::MessageLoop> CreateMessageLoop() override {
-    return nullptr;

[fdoray, 2017/05/10 16:53:50]

Returning nullptr prevented initialization of a MessageLoop by the base class,
which was required for the TestBrowserThreadBundle member below. This is no
longer required now that TestBrowserThreadBundle can cohabit with
ScopedTaskEnvironment.
https://chromium.googlesource.com/chromium/src/+/8c5805290290f2e7749c27ee7ea0...

-  }
-
   const base::FilePath& temp_path() { return temp_path_.GetPath(); }
 
   base::FilePath FirstEntryInDir() {
     base::FileEnumerator enumerator(
         temp_path(), false /* recursive */,
         base::FileEnumerator::FILES | base::FileEnumerator::DIRECTORIES);
     return enumerator.Next();
   }
 
   void DoTestPut(LocalStorageContextMojo* context,
@@ skipping 145 matching lines @@
   base::RunLoop().RunUntilIdle();
 
   // Data should have been preserved now.
   context = base::MakeUnique<LocalStorageContextMojo>(
       connector(), nullptr, base::FilePath(), test_path);
   EXPECT_TRUE(DoTestGet(context.get(), key, &result));
   EXPECT_EQ(value, result);
 }
 
 }  // namespace content