Switch to composition for TestBrowserThread.

This avoids exposing BrowserThreadImpl internals outside of content/,
and goes most of the way to not exposing the fact that underneath, it
is a base::Thread.  There are only three test files that use the
TestBrowserThread::DeprecatedGetThreadObject method.

TBR=owners
BUG=98716

Review URL: http://codereview.chromium.org/8440039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@108452 0039d316-1c4b-4281-b951-d872f2087c98

21 files changed, 124 insertions, 77 deletions

diff --git a/chrome/browser/autofill/autofill_download_unittest.cc b/chrome/browser/autofill/autofill_download_unittest.cc
index b90ce98..c8919cc 100644
--- a/chrome/browser/autofill/autofill_download_unittest.cc
+++ b/chrome/browser/autofill/autofill_download_unittest.cc
@@ -71,9 +71,7 @@ class AutofillDownloadTest : public AutofillDownloadManager::Observer,
   }
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
     profile_.CreateRequestContext();
   }
 
@@ -135,8 +133,7 @@ class AutofillDownloadTest : public AutofillDownloadManager::Observer,
   AutofillDownloadManager download_manager_;
 
  private:
-  // |request_context_getter_| must be released on the IO thread.
-  MessageLoop* io_thread_loop() { return io_thread_.message_loop(); }
+  // The profile's request context must be released on the IO thread.
   content::TestBrowserThread io_thread_;
 };
 
diff --git a/chrome/browser/component_updater/component_updater_service_unittest.cc b/chrome/browser/component_updater/component_updater_service_unittest.cc
index 3bbac3d..b080cca 100644
--- a/chrome/browser/component_updater/component_updater_service_unittest.cc
+++ b/chrome/browser/component_updater/component_updater_service_unittest.cc
@@ -232,7 +232,7 @@ TEST_F(ComponentUpdaterTest, CheckCrxSleep) {
   content::TestBrowserThread file_thread(BrowserThread::FILE);
   content::TestBrowserThread io_thread(BrowserThread::IO);
 
-  io_thread.StartWithOptions(base::Thread::Options(MessageLoop::TYPE_IO, 0));
+  io_thread.StartIOThread();
   file_thread.Start();
 
   scoped_refptr<ComponentUpdateInterceptor>
@@ -316,7 +316,7 @@ TEST_F(ComponentUpdaterTest, InstallCrx) {
   content::TestBrowserThread file_thread(BrowserThread::FILE);
   content::TestBrowserThread io_thread(BrowserThread::IO);
 
-  io_thread.StartWithOptions(base::Thread::Options(MessageLoop::TYPE_IO, 0));
+  io_thread.StartIOThread();
   file_thread.Start();
 
   scoped_refptr<ComponentUpdateInterceptor>
@@ -382,7 +382,7 @@ TEST_F(ComponentUpdaterTest, ProdVersionCheck) {
   content::TestBrowserThread file_thread(BrowserThread::FILE);
   content::TestBrowserThread io_thread(BrowserThread::IO);
 
-  io_thread.StartWithOptions(base::Thread::Options(MessageLoop::TYPE_IO, 0));
+  io_thread.StartIOThread();
   file_thread.Start();
 
   scoped_refptr<ComponentUpdateInterceptor>
diff --git a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
index 72eac2a..2db0f1e 100644
--- a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
+++ b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
@@ -233,13 +233,10 @@ class ProtocolHandlerRegistryTest : public testing::Test {
     ui_thread_.reset(new content::TestBrowserThread(BrowserThread::UI,
                                                     MessageLoop::current()));
     io_thread_.reset(new content::TestBrowserThread(BrowserThread::IO));
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_->StartWithOptions(options);
+    io_thread_->StartIOThread();
 
     file_thread_.reset(new content::TestBrowserThread(BrowserThread::FILE));
-    options.message_loop_type = MessageLoop::TYPE_DEFAULT;
-    file_thread_->StartWithOptions(options);
+    file_thread_->Start();
 
     profile_.reset(new TestingProfile());
     profile_->SetPrefService(new TestingPrefService());
diff --git a/chrome/browser/download/download_item_unittest.cc b/chrome/browser/download/download_item_unittest.cc
index 694f584..c2757e9 100644
--- a/chrome/browser/download/download_item_unittest.cc
+++ b/chrome/browser/download/download_item_unittest.cc
@@ -68,7 +68,7 @@ class DownloadItemTest : public testing::Test {
     // to ensure that all resources are cleaned up before the test exits.
     download_manager_ = NULL;
     profile_.reset(NULL);
-    ui_thread_.message_loop()->RunAllPending();
+    ui_thread_.DeprecatedGetThreadObject()->message_loop()->RunAllPending();
   }
 
   DownloadItem* CreateDownloadItem(DownloadItem::DownloadState state) {
diff --git a/chrome/browser/external_protocol/external_protocol_handler_unittest.cc b/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
index 51d5ff2..74bb856 100644
--- a/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
+++ b/chrome/browser/external_protocol/external_protocol_handler_unittest.cc
@@ -99,9 +99,7 @@ class ExternalProtocolHandlerTest : public testing::Test {
         file_thread_(BrowserThread::FILE) {}
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_DEFAULT;
-    file_thread_.StartWithOptions(options);
+    file_thread_.Start();
   }
 
   void DoTest(ExternalProtocolHandler::BlockState block_state,
diff --git a/chrome/browser/net/sqlite_persistent_cookie_store_unittest.cc b/chrome/browser/net/sqlite_persistent_cookie_store_unittest.cc
index b92a202..fcb60e3 100644
--- a/chrome/browser/net/sqlite_persistent_cookie_store_unittest.cc
+++ b/chrome/browser/net/sqlite_persistent_cookie_store_unittest.cc
@@ -189,17 +189,19 @@ TEST_F(SQLitePersistentCookieStoreTest, TestLoadCookiesForKey) {
     temp_dir_.path().Append(chrome::kCookieFilename));
   // Posting a blocking task to db_thread_ makes sure that the DB thread waits
   // until both Load and LoadCookiesForKey have been posted to its task queue.
-  db_thread_.PostTask(BrowserThread::DB, FROM_HERE,
-    base::Bind(&SQLitePersistentCookieStoreTest::WaitOnDBEvent,
-               base::Unretained(this)));
+  BrowserThread::PostTask(
+      BrowserThread::DB, FROM_HERE,
+      base::Bind(&SQLitePersistentCookieStoreTest::WaitOnDBEvent,
+                 base::Unretained(this)));
   store_->Load(base::Bind(&SQLitePersistentCookieStoreTest::OnLoaded,
                           base::Unretained(this)));
   store_->LoadCookiesForKey("aaa.com",
     base::Bind(&SQLitePersistentCookieStoreTest::OnKeyLoaded,
                base::Unretained(this)));
-  db_thread_.PostTask(BrowserThread::DB, FROM_HERE,
-    base::Bind(&SQLitePersistentCookieStoreTest::WaitOnDBEvent,
-               base::Unretained(this)));
+  BrowserThread::PostTask(
+      BrowserThread::DB, FROM_HERE,
+      base::Bind(&SQLitePersistentCookieStoreTest::WaitOnDBEvent,
+                 base::Unretained(this)));
 
   // Now the DB-thread queue contains:
   // (active:)
diff --git a/chrome/browser/safe_browsing/malware_details_unittest.cc b/chrome/browser/safe_browsing/malware_details_unittest.cc
index d6e253f..024fe9c 100644
--- a/chrome/browser/safe_browsing/malware_details_unittest.cc
+++ b/chrome/browser/safe_browsing/malware_details_unittest.cc
@@ -177,8 +177,7 @@ class MalwareDetailsTest : public ChromeRenderViewHostTestHarness {
   virtual void SetUp() {
     ChromeRenderViewHostTestHarness::SetUp();
     // The URLFetcher checks that the messageloop type is IO.
-    ASSERT_TRUE(io_thread_.StartWithOptions(
-        base::Thread::Options(MessageLoop::TYPE_IO, 0)));
+    ASSERT_TRUE(io_thread_.StartIOThread());
 
     profile()->CreateHistoryService(true /* delete_file */, false /* no_db */);
   }
diff --git a/chrome/browser/search_engines/template_url_service_test_util.cc b/chrome/browser/search_engines/template_url_service_test_util.cc
index 7d33f56..a7a3390 100644
--- a/chrome/browser/search_engines/template_url_service_test_util.cc
+++ b/chrome/browser/search_engines/template_url_service_test_util.cc
@@ -65,9 +65,7 @@ class TemplateURLServiceTestingProfile : public TestingProfile {
   // Starts the I/O thread. This isn't done automatically because not every test
   // needs this.
   void StartIOThread() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
   }
 
   virtual WebDataService* GetWebDataService(ServiceAccessType access) {
diff --git a/chrome/browser/sync/abstract_profile_sync_service_test.cc b/chrome/browser/sync/abstract_profile_sync_service_test.cc
index a38dae2..56f2e9c 100644
--- a/chrome/browser/sync/abstract_profile_sync_service_test.cc
+++ b/chrome/browser/sync/abstract_profile_sync_service_test.cc
@@ -105,9 +105,7 @@ AbstractProfileSyncServiceTest::~AbstractProfileSyncServiceTest() {}
 
 void AbstractProfileSyncServiceTest::SetUp() {
   db_thread_.Start();
-  base::Thread::Options options;
-  options.message_loop_type = MessageLoop::TYPE_IO;
-  io_thread_.StartWithOptions(options);
+  io_thread_.StartIOThread();
 }
 
 void AbstractProfileSyncServiceTest::TearDown() {
diff --git a/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc b/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
index 27c545e..290661e 100644
--- a/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
+++ b/chrome/browser/sync/glue/autofill_data_type_controller_unittest.cc
@@ -116,7 +116,8 @@ class AutofillDataTypeControllerTest : public testing::Test {
 
   virtual void SetUp() {
     db_thread_.Start();
-    db_notification_service_ = new ThreadNotificationService(&db_thread_);
+    db_notification_service_ = new ThreadNotificationService(
+        db_thread_.DeprecatedGetThreadObject());
     db_notification_service_->Init();
     web_data_service_ = new WebDataServiceFake();
     EXPECT_CALL(profile_, GetProfileSyncService()).WillRepeatedly(
@@ -162,7 +163,8 @@ TEST_F(AutofillDataTypeControllerTest, StartWDSNotReady) {
   autofill_dtc_->set_state(DataTypeController::MODEL_STARTING);
   EXPECT_FALSE(autofill_dtc_->StartModels());
 
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&ui_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      ui_thread_.DeprecatedGetThreadObject()));
   autofill_dtc_->Observe(
       chrome::NOTIFICATION_WEB_DATABASE_LOADED,
       content::Source<WebDataService>(web_data_service_.get()),
diff --git a/chrome/browser/sync/glue/http_bridge_unittest.cc b/chrome/browser/sync/glue/http_bridge_unittest.cc
index deb60de..0c5e3b4 100644
--- a/chrome/browser/sync/glue/http_bridge_unittest.cc
+++ b/chrome/browser/sync/glue/http_bridge_unittest.cc
@@ -29,13 +29,11 @@ class HttpBridgeTest : public testing::Test {
   }
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
   }
 
   virtual void TearDown() {
-    io_thread_loop()->ReleaseSoon(FROM_HERE,
+    GetIOThreadLoop()->ReleaseSoon(FROM_HERE,
         fake_default_request_context_getter_);
     io_thread_.Stop();
     fake_default_request_context_getter_ = NULL;
@@ -70,7 +68,9 @@ class HttpBridgeTest : public testing::Test {
     main_message_loop->PostTask(FROM_HERE, new MessageLoop::QuitTask);
   }
 
-  MessageLoop* io_thread_loop() { return io_thread_.message_loop(); }
+  MessageLoop* GetIOThreadLoop() {
+    return io_thread_.DeprecatedGetThreadObject()->message_loop();
+  }
 
   // Note this is lazy created, so don't call this before your bridge.
   TestURLRequestContextGetter* GetTestRequestContextGetter() {
@@ -102,20 +102,20 @@ class ShuntedHttpBridge : public HttpBridge {
                    test_(test), never_finishes_(never_finishes) { }
  protected:
   virtual void MakeAsynchronousPost() {
-    ASSERT_TRUE(MessageLoop::current() == test_->io_thread_loop());
+    ASSERT_TRUE(MessageLoop::current() == test_->GetIOThreadLoop());
     if (never_finishes_)
       return;
 
     // We don't actually want to make a request for this test, so just callback
     // as if it completed.
-    test_->io_thread_loop()->PostTask(FROM_HERE,
+    test_->GetIOThreadLoop()->PostTask(FROM_HERE,
         NewRunnableMethod(this, &ShuntedHttpBridge::CallOnURLFetchComplete));
   }
  private:
   ~ShuntedHttpBridge() {}
 
   void CallOnURLFetchComplete() {
-    ASSERT_TRUE(MessageLoop::current() == test_->io_thread_loop());
+    ASSERT_TRUE(MessageLoop::current() == test_->GetIOThreadLoop());
     // We return no cookies and a dummy content response.
     net::ResponseCookies cookies;
 
diff --git a/chrome/browser/sync/glue/sync_backend_host_unittest.cc b/chrome/browser/sync/glue/sync_backend_host_unittest.cc
index b8812ff..cea326a 100644
--- a/chrome/browser/sync/glue/sync_backend_host_unittest.cc
+++ b/chrome/browser/sync/glue/sync_backend_host_unittest.cc
@@ -59,9 +59,7 @@ class SyncBackendHostTest : public testing::Test {
   virtual ~SyncBackendHostTest() {}
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
   }
 
   virtual void TearDown() {
diff --git a/chrome/browser/sync/notifier/non_blocking_invalidation_notifier_unittest.cc b/chrome/browser/sync/notifier/non_blocking_invalidation_notifier_unittest.cc
index 90e21a4..1d934ca 100644
--- a/chrome/browser/sync/notifier/non_blocking_invalidation_notifier_unittest.cc
+++ b/chrome/browser/sync/notifier/non_blocking_invalidation_notifier_unittest.cc
@@ -35,7 +35,7 @@ class NonBlockingInvalidationNotifierTest : public testing::Test {
   virtual void SetUp() {
     base::Thread::Options options;
     options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
     request_context_getter_ = new TestURLRequestContextGetter;
     notifier::NotifierOptions notifier_options;
     notifier_options.request_context_getter = request_context_getter_;
diff --git a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
index 464c382..3535570 100644
--- a/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_autofill_unittest.cc
@@ -354,7 +354,8 @@ class ProfileSyncServiceAutofillTest : public AbstractProfileSyncServiceTest {
         WillRepeatedly(Return(web_data_service_.get()));
     personal_data_manager_->Init(&profile_);
 
-    notification_service_ = new ThreadNotificationService(&db_thread_);
+    notification_service_ = new ThreadNotificationService(
+        db_thread_.DeprecatedGetThreadObject());
     notification_service_->Init();
 
     // Note: This must be called *after* the notification service is created.
@@ -943,7 +944,8 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddEntry) {
 
   AutofillChangeList changes;
   changes.push_back(AutofillChange(AutofillChange::ADD, added_entry.key()));
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      db_thread_.DeprecatedGetThreadObject()));
   notifier->Notify(chrome::NOTIFICATION_AUTOFILL_ENTRIES_CHANGED,
                    content::Source<WebDataService>(web_data_service_.get()),
                    content::Details<AutofillChangeList>(&changes));
@@ -972,7 +974,8 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeAddProfile) {
 
   AutofillProfileChange change(AutofillProfileChange::ADD,
       added_profile.guid(), &added_profile);
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      db_thread_.DeprecatedGetThreadObject()));
   notifier->Notify(chrome::NOTIFICATION_AUTOFILL_PROFILE_CHANGED,
                    content::Source<WebDataService>(web_data_service_.get()),
                    content::Details<AutofillProfileChange>(&change));
@@ -1005,7 +1008,8 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeUpdateEntry) {
   AutofillChangeList changes;
   changes.push_back(AutofillChange(AutofillChange::UPDATE,
                                    updated_entry.key()));
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      db_thread_.DeprecatedGetThreadObject()));
   notifier->Notify(chrome::NOTIFICATION_AUTOFILL_ENTRIES_CHANGED,
                    content::Source<WebDataService>(web_data_service_.get()),
                    content::Details<AutofillChangeList>(&changes));
@@ -1034,7 +1038,8 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveEntry) {
   AutofillChangeList changes;
   changes.push_back(AutofillChange(AutofillChange::REMOVE,
                                    original_entry.key()));
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      db_thread_.DeprecatedGetThreadObject()));
   notifier->Notify(chrome::NOTIFICATION_AUTOFILL_ENTRIES_CHANGED,
                    content::Source<WebDataService>(web_data_service_.get()),
                    content::Details<AutofillChangeList>(&changes));
@@ -1072,7 +1077,8 @@ TEST_F(ProfileSyncServiceAutofillTest, ProcessUserChangeRemoveProfile) {
 
   AutofillProfileChange change(AutofillProfileChange::REMOVE,
                                sync_profile.guid(), NULL);
-  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(&db_thread_));
+  scoped_refptr<ThreadNotifier> notifier(new ThreadNotifier(
+      db_thread_.DeprecatedGetThreadObject()));
   notifier->Notify(chrome::NOTIFICATION_AUTOFILL_PROFILE_CHANGED,
                    content::Source<WebDataService>(web_data_service_.get()),
                    content::Details<AutofillProfileChange>(&change));
diff --git a/chrome/browser/sync/profile_sync_service_password_unittest.cc b/chrome/browser/sync/profile_sync_service_password_unittest.cc
index cd59234..50dfed69 100644
--- a/chrome/browser/sync/profile_sync_service_password_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_password_unittest.cc
@@ -162,7 +162,8 @@ class ProfileSyncServicePasswordTest : public AbstractProfileSyncServiceTest {
     profile_.CreateRequestContext();
     password_store_ = new MockPasswordStore();
 
-    notification_service_ = new ThreadNotificationService(&db_thread_);
+    notification_service_ = new ThreadNotificationService(
+        db_thread_.DeprecatedGetThreadObject());
     notification_service_->Init();
     registrar_.Add(&observer_,
         chrome::NOTIFICATION_SYNC_CONFIGURE_DONE,
diff --git a/chrome/browser/sync/profile_sync_service_session_unittest.cc b/chrome/browser/sync/profile_sync_service_session_unittest.cc
index ed25ad0..f5aac7b 100644
--- a/chrome/browser/sync/profile_sync_service_session_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_session_unittest.cc
@@ -166,9 +166,7 @@ class ProfileSyncServiceSessionTest
   virtual void SetUp() {
     // BrowserWithTestWindowTest implementation.
     BrowserWithTestWindowTest::SetUp();
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
     profile()->CreateRequestContext();
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
     SessionService* session_service = new SessionService(temp_dir_.path());
diff --git a/chrome/browser/sync/profile_sync_service_startup_unittest.cc b/chrome/browser/sync/profile_sync_service_startup_unittest.cc
index 674c423..400ffcc 100644
--- a/chrome/browser/sync/profile_sync_service_startup_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_startup_unittest.cc
@@ -44,9 +44,7 @@ class ProfileSyncServiceStartupTest : public testing::Test {
   }
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
     profile_->CreateRequestContext();
     CreateSyncService();
     service_->AddObserver(&observer_);
diff --git a/chrome/browser/sync/profile_sync_service_unittest.cc b/chrome/browser/sync/profile_sync_service_unittest.cc
index 376687f..470ba48 100644
--- a/chrome/browser/sync/profile_sync_service_unittest.cc
+++ b/chrome/browser/sync/profile_sync_service_unittest.cc
@@ -49,9 +49,7 @@ class ProfileSyncServiceTest : public testing::Test {
   virtual ~ProfileSyncServiceTest() {}
 
   virtual void SetUp() {
-    base::Thread::Options options;
-    options.message_loop_type = MessageLoop::TYPE_IO;
-    io_thread_.StartWithOptions(options);
+    io_thread_.StartIOThread();
     profile_.reset(new TestingProfile());
     profile_->CreateRequestContext();
 
diff --git a/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc b/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
index b719f37..3bd0694 100644
--- a/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
+++ b/chrome/browser/sync/util/extensions_activity_monitor_unittest.cc
@@ -115,18 +115,16 @@ class ExtensionsActivityMonitorTest : public testing::Test {
   virtual void SetUp() {
     ui_thread_.Start();
     base::WaitableEvent service_created(false, false);
-    ui_thread_.message_loop()->PostTask(FROM_HERE,
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
         new DoUIThreadSetupTask(&service_, &service_created));
     service_created.Wait();
   }
 
   virtual void TearDown() {
-    ui_thread_.message_loop()->DeleteSoon(FROM_HERE, service_);
+    BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, service_);
     ui_thread_.Stop();
   }
 
-  MessageLoop* ui_loop() { return ui_thread_.message_loop(); }
-
   static std::string GetExtensionIdForPath(
       const FilePath::StringType& extension_path) {
     std::string error;
@@ -182,7 +180,7 @@ TEST_F(ExtensionsActivityMonitorTest, Basic) {
   EXPECT_EQ(writes_by_extension1, results[id1].bookmark_write_count);
   EXPECT_EQ(writes_by_extension2, results[id2].bookmark_write_count);
 
-  ui_loop()->DeleteSoon(FROM_HERE, monitor);
+  BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, monitor);
 }
 
 TEST_F(ExtensionsActivityMonitorTest, Put) {
@@ -219,7 +217,7 @@ TEST_F(ExtensionsActivityMonitorTest, Put) {
   EXPECT_EQ(id2, new_records[id2].extension_id);
   EXPECT_EQ(5U, new_records[id1].bookmark_write_count);
   EXPECT_EQ(8U + 2U, new_records[id2].bookmark_write_count);
-  ui_loop()->DeleteSoon(FROM_HERE, monitor);
+  BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, monitor);
 }
 
 TEST_F(ExtensionsActivityMonitorTest, MultiGet) {
@@ -246,5 +244,5 @@ TEST_F(ExtensionsActivityMonitorTest, MultiGet) {
   EXPECT_EQ(1U, results.size());
   EXPECT_EQ(3U, results[id1].bookmark_write_count);
 
-  ui_loop()->DeleteSoon(FROM_HERE, monitor);
+  BrowserThread::DeleteSoon(BrowserThread::UI, FROM_HERE, monitor);
 }
diff --git a/content/test/test_browser_thread.cc b/content/test/test_browser_thread.cc
index ca90930..f3e6cc8 100644
--- a/content/test/test_browser_thread.cc
+++ b/content/test/test_browser_thread.cc
@@ -4,18 +4,44 @@
 
 #include "content/test/test_browser_thread.h"
 
+#include "base/threading/thread.h"
+#include "content/browser/browser_thread_impl.h"
+
 namespace content {
 
-TestBrowserThread::TestBrowserThread(ID identifier)
-    : BrowserThreadImpl(identifier) {
+TestBrowserThread::TestBrowserThread(BrowserThread::ID identifier)
+    : impl(new BrowserThreadImpl(identifier)) {
 }
 
-TestBrowserThread::TestBrowserThread(ID identifier, MessageLoop* message_loop)
-    : BrowserThreadImpl(identifier, message_loop) {
+TestBrowserThread::TestBrowserThread(BrowserThread::ID identifier,
+                                     MessageLoop* message_loop)
+    : impl(new BrowserThreadImpl(identifier, message_loop)) {
 }
 
 TestBrowserThread::~TestBrowserThread() {
   Stop();
 }
 
+bool TestBrowserThread::Start() {
+  return impl->Start();
+}
+
+bool TestBrowserThread::StartIOThread() {
+  base::Thread::Options options;
+  options.message_loop_type = MessageLoop::TYPE_IO;
+  return impl->StartWithOptions(options);
+}
+
+void TestBrowserThread::Stop() {
+  impl->Stop();
+}
+
+bool TestBrowserThread::IsRunning() {
+  return impl->IsRunning();
+}
+
+base::Thread* TestBrowserThread::DeprecatedGetThreadObject() {
+  return impl.get();
+}
+
 }  // namespace content
diff --git a/content/test/test_browser_thread.h b/content/test/test_browser_thread.h
index 1067f9e..06e632f 100644
--- a/content/test/test_browser_thread.h
+++ b/content/test/test_browser_thread.h
@@ -6,17 +6,50 @@
 #define CONTENT_TEST_TEST_BROWSER_BROWSER_THREAD_H_
 #pragma once
 
-#include "content/browser/browser_thread_impl.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/public/browser/browser_thread.h"
+
+class MessageLoop;
+
+namespace base {
+class Thread;
+}
 
 namespace content {
 
+class BrowserThreadImpl;
+
 // A BrowserThread for unit tests; this lets unit tests in chrome/
 // create BrowserThread instances.
-class TestBrowserThread : public BrowserThreadImpl {
+class TestBrowserThread {
  public:
-  explicit TestBrowserThread(ID identifier);
-  TestBrowserThread(ID identifier, MessageLoop* message_loop);
-  virtual ~TestBrowserThread();
+  explicit TestBrowserThread(BrowserThread::ID identifier);
+  TestBrowserThread(BrowserThread::ID identifier, MessageLoop* message_loop);
+  ~TestBrowserThread();
+
+  // We provide a subset of the capabilities of the Thread interface
+  // to enable certain unit tests.  To avoid a stronger dependency of
+  // the internals of BrowserThread, we do not provide the full Thread
+  // interface.
+
+  // Starts the thread with a generic message loop.
+  bool Start();
+
+  // Starts the thread with an IOThread message loop.
+  bool StartIOThread();
+
+  // Stops the thread.
+  void Stop();
+
+  // Returns true if the thread is running.
+  bool IsRunning();
+
+  // Returns a Thread pointer for the thread. This should not be used
+  // in new tests.
+  base::Thread* DeprecatedGetThreadObject();
+
+ private:
+  scoped_ptr<BrowserThreadImpl> impl;
 };
 
 }  // namespace content