Use TestingProfile::Builder::AddTestingFactory at ChromeRenderViewHostTestHarness

components/browser_context_keyed_service/browser_context_keyed_service_factory.h

 // 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.
 
 #ifndef COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_BROWSER_CONTEXT_KEYED_SERVICE_FACTORY_H_
 #define COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_BROWSER_CONTEXT_KEYED_SERVICE_FACTORY_H_
 
 #include <map>
 
 #include "base/basictypes.h"
@@ skipping 28 matching lines @@
   void SetTestingFactory(content::BrowserContext* context,
                          TestingFactoryFunction factory);
 
   // Associates |factory| with |context| and immediately returns the created
   // BrowserContextKeyedService. Since the factory will be used immediately,
   // it may not be NULL.
   BrowserContextKeyedService* SetTestingFactoryAndUse(
       content::BrowserContext* context,
       TestingFactoryFunction factory);
 
+  // Removes the testing factory associated with |context|, if there is one.
+  // This can be used by tests that require a service that isn't created for
+  // tests by default (because its factory returns true from
+  // ServiceIsNULLWhileTesting).
+  void RemoveTestingFactory(content::BrowserContext* context);

[Paweł Hajdan Jr., 2014/03/07 22:08:12]

This can easily make the code harder to follow. Can we avoid setting the testing
factory to something unwanted in the first place?

[Joao da Silva, 2014/03/07 23:29:20]

That would be great, can you suggest a way to do it?

Note that the factory isn't being set by a test directly;
BrowserContextDependencyManager::DoCreateBrowserContextServices() calls
SetEmptyTestingFactory() when ServiceIsNULLWhileTesting is true, which sets a
NULL factory; that's what's getting cleared here.

+
  protected:
   // BrowserContextKeyedServiceFactories must communicate with a
   // BrowserContextDependencyManager. For all non-test code, write your subclass
   // constructors like this:
   //
   //   MyServiceFactory::MyServiceFactory()
   //     : BrowserContextKeyedServiceFactory(
   //         "MyService",
   //         BrowserContextDependencyManager::GetInstance())
   //   {}
@@ skipping 58 matching lines @@
   BrowserContextKeyedServices mapping_;
 
   // The mapping between a BrowserContext and its overridden
   // TestingFactoryFunction.
   BrowserContextOverriddenTestingFunctions testing_factories_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserContextKeyedServiceFactory);
 };
 
 #endif  // COMPONENTS_BROWSER_CONTEXT_KEYED_SERVICE_BROWSER_CONTEXT_KEYED_SERVICE_FACTORY_H_