Set the Feature's ChannelForTesting to Trunk during extension tests, so that

chrome/common/extensions/manifest_tests/extension_manifests_background_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 "chrome/common/extensions/manifest_tests/extension_manifest_test.h"
 
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_error_utils.h"
 #include "chrome/common/extensions/extension_manifest_constants.h"
+#include "chrome/common/extensions/features/feature.h"
 #include "chrome/common/extensions/features/simple_feature_provider.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace errors = extension_manifest_errors;
 
 namespace extensions {
 
 TEST_F(ExtensionManifestTest, BackgroundPermission) {
   LoadAndExpectError("background_permission.json",
                      errors::kBackgroundPermissionNeeded);
@@ skipping 57 matching lines @@
   EXPECT_FALSE(extension->allow_background_js_access());
 
   extension = LoadAndExpectSuccess("background_allow_no_js_access2.json");
   ASSERT_TRUE(extension);
   EXPECT_FALSE(extension->allow_background_js_access());
 }
 
 TEST_F(ExtensionManifestTest, BackgroundPageWebRequest) {
   CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kEnableExperimentalExtensionApis);
+  Feature::SetChannelForTesting(chrome::VersionInfo::CHANNEL_UNKNOWN);
 
   std::string error;
   scoped_ptr<DictionaryValue> manifest(
       LoadManifestFile("background_page.json", &error));
   ASSERT_TRUE(manifest.get());
   manifest->SetBoolean(keys::kBackgroundPersistent, false);
   manifest->SetInteger(keys::kManifestVersion, 2);
   scoped_refptr<Extension> extension(
       LoadAndExpectSuccess(Manifest(manifest.get(), "")));
   ASSERT_TRUE(extension);
   EXPECT_TRUE(extension->has_lazy_background_page());
 
   ListValue* permissions = new ListValue();
   permissions->Append(Value::CreateStringValue("webRequest"));
   manifest->Set(keys::kPermissions, permissions);
   LoadAndExpectError(Manifest(manifest.get(), ""),
                      errors::kWebRequestConflictsWithLazyBackground);
 }
 
 }  // namespace extensions