Removes MessageLoop::TYPE_XXX where possible

This is part of attempting to get rid of MessageLoop::Type enum.

BUG=none
TEST=none
R=darin@chromium.org

Review URL: https://codereview.chromium.org/136683004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244996 0039d316-1c4b-4281-b951-d872f2087c98

58 files changed, 122 insertions, 151 deletions

diff --git a/android_webview/browser/net/android_stream_reader_url_request_job_unittest.cc b/android_webview/browser/net/android_stream_reader_url_request_job_unittest.cc
index 651726b..f09b5c5 100644
--- a/android_webview/browser/net/android_stream_reader_url_request_job_unittest.cc
+++ b/android_webview/browser/net/android_stream_reader_url_request_job_unittest.cc
@@ -147,7 +147,7 @@ class TestStreamReaderJob : public AndroidStreamReaderURLRequestJob {
 
 class AndroidStreamReaderURLRequestJobTest : public Test {
  public:
-  AndroidStreamReaderURLRequestJobTest() : loop_(base::MessageLoop::TYPE_IO) {}
+  AndroidStreamReaderURLRequestJobTest() {}
 
  protected:
   virtual void SetUp() {
@@ -195,7 +195,7 @@ class AndroidStreamReaderURLRequestJobTest : public Test {
     DCHECK(set_protocol);
   }
 
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   TestURLRequestContext context_;
   android_webview::AwURLRequestJobFactory factory_;
   TestDelegate url_request_delegate_;
diff --git a/base/cancelable_callback_unittest.cc b/base/cancelable_callback_unittest.cc
index 89c603c..fcbe23c 100644
--- a/base/cancelable_callback_unittest.cc
+++ b/base/cancelable_callback_unittest.cc
@@ -159,7 +159,7 @@ TEST(CancelableCallbackTest, IsNull) {
 // CancelableCallback posted to a MessageLoop with PostTask.
 //  - Callbacks posted to a MessageLoop can be cancelled.
 TEST(CancelableCallbackTest, PostTask) {
-  MessageLoop loop(MessageLoop::TYPE_DEFAULT);
+  MessageLoop loop;
 
   int count = 0;
   CancelableClosure cancelable(base::Bind(&Increment,
diff --git a/base/files/file_util_proxy_unittest.cc b/base/files/file_util_proxy_unittest.cc
index 762d92b0..d01d56d 100644
--- a/base/files/file_util_proxy_unittest.cc
+++ b/base/files/file_util_proxy_unittest.cc
@@ -21,8 +21,7 @@ namespace base {
 class FileUtilProxyTest : public testing::Test {
  public:
   FileUtilProxyTest()
-      : message_loop_(MessageLoop::TYPE_IO),
-        file_thread_("FileUtilProxyTestFileThread"),
+      : file_thread_("FileUtilProxyTestFileThread"),
         error_(PLATFORM_FILE_OK),
         created_(false),
         file_(kInvalidPlatformFileValue),
@@ -103,7 +102,7 @@ class FileUtilProxyTest : public testing::Test {
   const FilePath& test_dir_path() const { return dir_.path(); }
   const FilePath test_path() const { return dir_.path().AppendASCII("test"); }
 
-  MessageLoop message_loop_;
+  MessageLoopForIO message_loop_;
   Thread file_thread_;
 
   ScopedTempDir dir_;
diff --git a/base/memory/discardable_memory_provider_unittest.cc b/base/memory/discardable_memory_provider_unittest.cc
index 7e84dc4..2050700 100644
--- a/base/memory/discardable_memory_provider_unittest.cc
+++ b/base/memory/discardable_memory_provider_unittest.cc
@@ -62,8 +62,7 @@ class DiscardableMemoryProviderTestBase {
   };
 
   DiscardableMemoryProviderTestBase()
-      : message_loop_(MessageLoop::TYPE_IO),
-        provider_(new internal::DiscardableMemoryProvider) {
+      : provider_(new internal::DiscardableMemoryProvider) {
     provider_->RegisterMemoryPressureListener();
   }
 
@@ -101,7 +100,7 @@ class DiscardableMemoryProviderTestBase {
   }
 
  private:
-  MessageLoop message_loop_;
+  MessageLoopForIO message_loop_;
   scoped_ptr<internal::DiscardableMemoryProvider> provider_;
 };
 
diff --git a/base/timer/timer_unittest.cc b/base/timer/timer_unittest.cc
index 728e861..0fb2b45 100644
--- a/base/timer/timer_unittest.cc
+++ b/base/timer/timer_unittest.cc
@@ -375,7 +375,7 @@ TEST(TimerTest, MessageLoopShutdown) {
     OneShotTimerTester c(&did_run);
     OneShotTimerTester d(&did_run);
     {
-      base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+      base::MessageLoop loop;
       a.Start();
       b.Start();
     }  // MessageLoop destructs by falling out of scope.
@@ -389,7 +389,7 @@ void TimerTestCallback() {
 
 TEST(TimerTest, NonRepeatIsRunning) {
   {
-    base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+    base::MessageLoop loop;
     base::Timer timer(false, false);
     EXPECT_FALSE(timer.IsRunning());
     timer.Start(FROM_HERE, TimeDelta::FromDays(1),
@@ -402,7 +402,7 @@ TEST(TimerTest, NonRepeatIsRunning) {
 
   {
     base::Timer timer(true, false);
-    base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+    base::MessageLoop loop;
     EXPECT_FALSE(timer.IsRunning());
     timer.Start(FROM_HERE, TimeDelta::FromDays(1),
                 base::Bind(&TimerTestCallback));
@@ -418,7 +418,7 @@ TEST(TimerTest, NonRepeatIsRunning) {
 TEST(TimerTest, NonRepeatMessageLoopDeath) {
   base::Timer timer(false, false);
   {
-    base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+    base::MessageLoop loop;
     EXPECT_FALSE(timer.IsRunning());
     timer.Start(FROM_HERE, TimeDelta::FromDays(1),
                 base::Bind(&TimerTestCallback));
@@ -429,7 +429,7 @@ TEST(TimerTest, NonRepeatMessageLoopDeath) {
 }
 
 TEST(TimerTest, RetainRepeatIsRunning) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop loop;
   base::Timer timer(FROM_HERE, TimeDelta::FromDays(1),
                     base::Bind(&TimerTestCallback), true);
   EXPECT_FALSE(timer.IsRunning());
@@ -442,7 +442,7 @@ TEST(TimerTest, RetainRepeatIsRunning) {
 }
 
 TEST(TimerTest, RetainNonRepeatIsRunning) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop loop;
   base::Timer timer(FROM_HERE, TimeDelta::FromDays(1),
                     base::Bind(&TimerTestCallback), false);
   EXPECT_FALSE(timer.IsRunning());
@@ -477,7 +477,7 @@ void SetCallbackHappened2() {
 TEST(TimerTest, ContinuationStopStart) {
   {
     ClearAllCallbackHappened();
-    base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+    base::MessageLoop loop;
     base::Timer timer(false, false);
     timer.Start(FROM_HERE, TimeDelta::FromMilliseconds(10),
                 base::Bind(&SetCallbackHappened1));
@@ -493,7 +493,7 @@ TEST(TimerTest, ContinuationStopStart) {
 TEST(TimerTest, ContinuationReset) {
   {
     ClearAllCallbackHappened();
-    base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+    base::MessageLoop loop;
     base::Timer timer(false, false);
     timer.Start(FROM_HERE, TimeDelta::FromMilliseconds(10),
                 base::Bind(&SetCallbackHappened1));
diff --git a/chrome/browser/chromeos/login/login_utils_browsertest.cc b/chrome/browser/chromeos/login/login_utils_browsertest.cc
index bd80739..825bbe0 100644
--- a/chrome/browser/chromeos/login/login_utils_browsertest.cc
+++ b/chrome/browser/chromeos/login/login_utils_browsertest.cc
@@ -148,7 +148,6 @@ class LoginUtilsTest : public testing::Test,
   LoginUtilsTest()
       : fake_io_thread_completion_(false, false),
         fake_io_thread_("fake_io_thread"),
-        loop_(base::MessageLoop::TYPE_IO),
         browser_process_(TestingBrowserProcess::GetGlobal()),
         local_state_(browser_process_),
         ui_thread_(BrowserThread::UI, &loop_),
@@ -455,7 +454,7 @@ class LoginUtilsTest : public testing::Test,
   base::WaitableEvent fake_io_thread_completion_;
   base::Thread fake_io_thread_;
 
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   TestingBrowserProcess* browser_process_;
   ScopedTestingLocalState local_state_;
 
diff --git a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
index f3e9941..d0bc463 100644
--- a/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
+++ b/chrome/browser/custom_handlers/protocol_handler_registry_unittest.cc
@@ -282,7 +282,7 @@ class QueryProtocolHandlerOnChange
 // our type based on the current thread. GO DEPENDENCY INJECTION!
 class TestMessageLoop : public base::MessageLoop {
  public:
-  TestMessageLoop() : base::MessageLoop(base::MessageLoop::TYPE_DEFAULT) {}
+  TestMessageLoop() {}
   virtual ~TestMessageLoop() {}
   virtual bool IsType(base::MessageLoop::Type type) const OVERRIDE {
     switch (type) {
diff --git a/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_attribute_unittest.cc b/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_attribute_unittest.cc
index b350afc..05c9d62 100644
--- a/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_attribute_unittest.cc
+++ b/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_attribute_unittest.cc
@@ -32,7 +32,7 @@ namespace keys = declarative_webrequest_constants;
 
 TEST(WebRequestConditionAttributeTest, CreateConditionAttribute) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   std::string error;
   scoped_refptr<const WebRequestConditionAttribute> result;
@@ -73,7 +73,7 @@ TEST(WebRequestConditionAttributeTest, CreateConditionAttribute) {
 
 TEST(WebRequestConditionAttributeTest, ResourceType) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   std::string error;
   base::ListValue resource_types;
@@ -106,7 +106,7 @@ TEST(WebRequestConditionAttributeTest, ResourceType) {
 
 TEST(WebRequestConditionAttributeTest, ContentType) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   std::string error;
   scoped_refptr<const WebRequestConditionAttribute> result;
@@ -177,7 +177,7 @@ TEST(WebRequestConditionAttributeTest, ContentType) {
 // Testing WebRequestConditionAttributeThirdParty.
 TEST(WebRequestConditionAttributeTest, ThirdParty) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   std::string error;
   const FundamentalValue value_true(true);
@@ -239,7 +239,7 @@ TEST(WebRequestConditionAttributeTest, ThirdParty) {
 // applicable in all stages.
 TEST(WebRequestConditionAttributeTest, Stages) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   typedef std::pair<RequestStage, const char*> StageNamePair;
   static const StageNamePair active_stages[] = {
@@ -418,7 +418,7 @@ void MatchAndCheck(const std::vector< std::vector<const std::string*> >& tests,
 // by both types of condition attributes, so it is enough to test it once.
 TEST(WebRequestConditionAttributeTest, RequestHeaders) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   net::TestURLRequestContext context;
   net::TestDelegate delegate;
@@ -498,7 +498,7 @@ TEST(WebRequestConditionAttributeTest, RequestHeaders) {
 // 3. Negating the match in case of 'doesNotContainHeaders'.
 TEST(WebRequestConditionAttributeTest, ResponseHeaders) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   net::SpawnedTestServer test_server(
       net::SpawnedTestServer::TYPE_HTTP,
diff --git a/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_unittest.cc b/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_unittest.cc
index d49a32d..63c9e1b 100644
--- a/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_unittest.cc
+++ b/chrome/browser/extensions/api/declarative_webrequest/webrequest_condition_unittest.cc
@@ -23,7 +23,7 @@ namespace extensions {
 
 TEST(WebRequestConditionTest, CreateCondition) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
 
   std::string error;
@@ -101,7 +101,7 @@ TEST(WebRequestConditionTest, CreateCondition) {
 
 TEST(WebRequestConditionTest, CreateConditionFirstPartyForCookies) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
 
   std::string error;
@@ -147,7 +147,7 @@ TEST(WebRequestConditionTest, CreateConditionFirstPartyForCookies) {
 //      always fulfilled.
 TEST(WebRequestConditionTest, NoUrlAttributes) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
   std::string error;
 
@@ -220,7 +220,7 @@ TEST(WebRequestConditionTest, NoUrlAttributes) {
 
 TEST(WebRequestConditionTest, CreateConditionSet) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
 
   WebRequestConditionSet::AnyVector conditions;
@@ -289,7 +289,7 @@ TEST(WebRequestConditionTest, CreateConditionSet) {
 
 TEST(WebRequestConditionTest, TestPortFilter) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
 
   WebRequestConditionSet::AnyVector conditions;
@@ -349,7 +349,7 @@ TEST(WebRequestConditionTest, TestPortFilter) {
 // impossible that both conditions are fulfilled at the same time.
 TEST(WebRequestConditionTest, ConditionsWithConflictingStages) {
   // Necessary for TestURLRequest.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
   URLMatcher matcher;
 
   std::string error;
diff --git a/chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry_unittest.cc b/chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry_unittest.cc
index 41a143a..7ef5524 100644
--- a/chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry_unittest.cc
+++ b/chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry_unittest.cc
@@ -81,8 +81,7 @@ class TestWebRequestRulesRegistry : public WebRequestRulesRegistry {
 class WebRequestRulesRegistryTest : public testing::Test {
  public:
   WebRequestRulesRegistryTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        ui_(content::BrowserThread::UI, &message_loop_),
+      : ui_(content::BrowserThread::UI, &message_loop_),
         io_(content::BrowserThread::IO, &message_loop_) {}
 
   virtual ~WebRequestRulesRegistryTest() {}
@@ -223,7 +222,7 @@ class WebRequestRulesRegistryTest : public testing::Test {
   }
 
  protected:
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   content::TestBrowserThread ui_;
   content::TestBrowserThread io_;
   // Two extensions with host permissions for all URLs and the DWR permission.
diff --git a/chrome/browser/extensions/api/dial/dial_service_unittest.cc b/chrome/browser/extensions/api/dial/dial_service_unittest.cc
index 02d5e09..e282a57 100644
--- a/chrome/browser/extensions/api/dial/dial_service_unittest.cc
+++ b/chrome/browser/extensions/api/dial/dial_service_unittest.cc
@@ -57,7 +57,7 @@ class DialServiceTest : public testing::Test {
 };
 
 TEST_F(DialServiceTest, TestSendMultipleRequests) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   // Setting the finish delay to zero disables the timer that invokes
   // FinishDiscovery().
   dial_service_.finish_delay_ = TimeDelta::FromSeconds(0);
@@ -74,7 +74,7 @@ TEST_F(DialServiceTest, TestSendMultipleRequests) {
 }
 
 TEST_F(DialServiceTest, TestMultipleNetworkInterfaces) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   // Setting the finish delay to zero disables the timer that invokes
   // FinishDiscovery().
   dial_service_.finish_delay_ = TimeDelta::FromSeconds(0);
diff --git a/chrome/browser/extensions/default_apps_unittest.cc b/chrome/browser/extensions/default_apps_unittest.cc
index 1032d37..d86e08f 100644
--- a/chrome/browser/extensions/default_apps_unittest.cc
+++ b/chrome/browser/extensions/default_apps_unittest.cc
@@ -29,11 +29,10 @@ class MockExternalLoader : public ExternalLoader {
 
 class DefaultAppsTest : public testing::Test {
  public:
-  DefaultAppsTest() : loop_(base::MessageLoop::TYPE_IO),
-      ui_thread_(content::BrowserThread::UI, &loop_) {}
+  DefaultAppsTest() : ui_thread_(content::BrowserThread::UI, &loop_) {}
   virtual ~DefaultAppsTest() {}
  private:
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   content::TestBrowserThread ui_thread_;
 };
 
diff --git a/chrome/browser/extensions/external_policy_loader_unittest.cc b/chrome/browser/extensions/external_policy_loader_unittest.cc
index 8f70dba..de36941 100644
--- a/chrome/browser/extensions/external_policy_loader_unittest.cc
+++ b/chrome/browser/extensions/external_policy_loader_unittest.cc
@@ -26,9 +26,7 @@ namespace extensions {
 
 class ExternalPolicyLoaderTest : public testing::Test {
  public:
-  ExternalPolicyLoaderTest()
-      : loop_(base::MessageLoop::TYPE_IO),
-        ui_thread_(BrowserThread::UI, &loop_) {
+  ExternalPolicyLoaderTest() : ui_thread_(BrowserThread::UI, &loop_) {
   }
 
   virtual ~ExternalPolicyLoaderTest() {}
@@ -36,7 +34,7 @@ class ExternalPolicyLoaderTest : public testing::Test {
  private:
   // We need these to satisfy BrowserThread::CurrentlyOn(BrowserThread::UI)
   // checks in ExternalProviderImpl.
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   content::TestBrowserThread ui_thread_;
 };
 
diff --git a/chrome/browser/importer/profile_writer_unittest.cc b/chrome/browser/importer/profile_writer_unittest.cc
index 8e77ac1..8b447a7 100644
--- a/chrome/browser/importer/profile_writer_unittest.cc
+++ b/chrome/browser/importer/profile_writer_unittest.cc
@@ -34,8 +34,7 @@ class TestProfileWriter : public ProfileWriter {
 class ProfileWriterTest : public testing::Test {
  public:
   ProfileWriterTest()
-      : loop_(base::MessageLoop::TYPE_DEFAULT),
-        ui_thread_(BrowserThread::UI, &loop_),
+      : ui_thread_(BrowserThread::UI, &loop_),
         file_thread_(BrowserThread::FILE, &loop_) {
   }
   virtual ~ProfileWriterTest() {}
diff --git a/chrome/browser/net/chrome_fraudulent_certificate_reporter_unittest.cc b/chrome/browser/net/chrome_fraudulent_certificate_reporter_unittest.cc
index 04e924b..f0de8dc 100644
--- a/chrome/browser/net/chrome_fraudulent_certificate_reporter_unittest.cc
+++ b/chrome/browser/net/chrome_fraudulent_certificate_reporter_unittest.cc
@@ -185,21 +185,21 @@ TEST(ChromeFraudulentCertificateReporterTest, GoodBadInfo) {
 }
 
 TEST(ChromeFraudulentCertificateReporterTest, ReportIsSent) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   content::TestBrowserThread io_thread(BrowserThread::IO, &loop);
   loop.PostTask(FROM_HERE, base::Bind(&DoReportIsSent));
   loop.RunUntilIdle();
 }
 
 TEST(ChromeFraudulentCertificateReporterTest, MockReportIsSent) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   content::TestBrowserThread io_thread(BrowserThread::IO, &loop);
   loop.PostTask(FROM_HERE, base::Bind(&DoMockReportIsSent));
   loop.RunUntilIdle();
 }
 
 TEST(ChromeFraudulentCertificateReporterTest, ReportIsNotSent) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   content::TestBrowserThread io_thread(BrowserThread::IO, &loop);
   loop.PostTask(FROM_HERE, base::Bind(&DoReportIsNotSent));
   loop.RunUntilIdle();
diff --git a/chrome/browser/net/connection_tester_unittest.cc b/chrome/browser/net/connection_tester_unittest.cc
index 812c692..6239c2b 100644
--- a/chrome/browser/net/connection_tester_unittest.cc
+++ b/chrome/browser/net/connection_tester_unittest.cc
@@ -89,8 +89,7 @@ class ConnectionTesterDelegate : public ConnectionTester::Delegate {
 class ConnectionTesterTest : public PlatformTest {
  public:
   ConnectionTesterTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        io_thread_(BrowserThread::IO, &message_loop_),
+      : io_thread_(BrowserThread::IO, &message_loop_),
         test_server_(net::SpawnedTestServer::TYPE_HTTP,
                      net::SpawnedTestServer::kLocalhost,
                      // Nothing is read in this directory.
@@ -105,7 +104,7 @@ class ConnectionTesterTest : public PlatformTest {
   // SSLClientAuthCache calls RemoveObserver when destroyed, but if the
   // MessageLoop is already destroyed, then the RemoveObserver will be a
   // no-op, and the ObserverList will contain invalid entries.
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   content::TestBrowserThread io_thread_;
   net::SpawnedTestServer test_server_;
   ConnectionTesterDelegate test_delegate_;
diff --git a/chrome/browser/policy/url_blacklist_manager_unittest.cc b/chrome/browser/policy/url_blacklist_manager_unittest.cc
index 4329cbd..cc66528 100644
--- a/chrome/browser/policy/url_blacklist_manager_unittest.cc
+++ b/chrome/browser/policy/url_blacklist_manager_unittest.cc
@@ -84,7 +84,7 @@ class TestingURLBlacklistManager : public URLBlacklistManager {
 
 class URLBlacklistManagerTest : public testing::Test {
  protected:
-  URLBlacklistManagerTest() : loop_(base::MessageLoop::TYPE_IO) {}
+  URLBlacklistManagerTest() {}
 
   virtual void SetUp() OVERRIDE {
     pref_service_.registry()->RegisterListPref(policy_prefs::kUrlBlacklist);
@@ -102,7 +102,7 @@ class URLBlacklistManagerTest : public testing::Test {
     blacklist_manager_.reset();
   }
 
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   TestingPrefServiceSimple pref_service_;
   scoped_ptr<TestingURLBlacklistManager> blacklist_manager_;
 };
diff --git a/chrome/browser/predictors/autocomplete_action_predictor_table_unittest.cc b/chrome/browser/predictors/autocomplete_action_predictor_table_unittest.cc
index fe75dd1..4cc47bd 100644
--- a/chrome/browser/predictors/autocomplete_action_predictor_table_unittest.cc
+++ b/chrome/browser/predictors/autocomplete_action_predictor_table_unittest.cc
@@ -71,8 +71,7 @@ class AutocompleteActionPredictorTableReopenTest
 };
 
 AutocompleteActionPredictorTableTest::AutocompleteActionPredictorTableTest()
-    : loop_(base::MessageLoop::TYPE_DEFAULT),
-      db_thread_(BrowserThread::DB, &loop_) {
+    : db_thread_(BrowserThread::DB, &loop_) {
 }
 
 AutocompleteActionPredictorTableTest::~AutocompleteActionPredictorTableTest() {
diff --git a/chrome/browser/predictors/autocomplete_action_predictor_unittest.cc b/chrome/browser/predictors/autocomplete_action_predictor_unittest.cc
index 13d681c..1fbe21d 100644
--- a/chrome/browser/predictors/autocomplete_action_predictor_unittest.cc
+++ b/chrome/browser/predictors/autocomplete_action_predictor_unittest.cc
@@ -83,8 +83,7 @@ namespace predictors {
 class AutocompleteActionPredictorTest : public testing::Test {
  public:
   AutocompleteActionPredictorTest()
-      : loop_(base::MessageLoop::TYPE_DEFAULT),
-        ui_thread_(BrowserThread::UI, &loop_),
+      : ui_thread_(BrowserThread::UI, &loop_),
         db_thread_(BrowserThread::DB, &loop_),
         file_thread_(BrowserThread::FILE, &loop_),
         profile_(new TestingProfile()),
diff --git a/chrome/browser/profile_resetter/profile_resetter_unittest.cc b/chrome/browser/profile_resetter/profile_resetter_unittest.cc
index 08f204a..91312aa 100644
--- a/chrome/browser/profile_resetter/profile_resetter_unittest.cc
+++ b/chrome/browser/profile_resetter/profile_resetter_unittest.cc
@@ -181,7 +181,7 @@ class ConfigParserTest : public testing::Test {
 
   MOCK_METHOD0(Callback, void(void));
 
-  base::MessageLoop loop_;
+  base::MessageLoopForIO loop_;
   content::TestBrowserThread ui_thread_;
   content::TestBrowserThread io_thread_;
   URLFetcherRequestListener request_listener_;
@@ -189,8 +189,7 @@ class ConfigParserTest : public testing::Test {
 };
 
 ConfigParserTest::ConfigParserTest()
-    : loop_(base::MessageLoop::TYPE_IO),
-      ui_thread_(content::BrowserThread::UI, &loop_),
+    : ui_thread_(content::BrowserThread::UI, &loop_),
       io_thread_(content::BrowserThread::IO, &loop_),
       factory_(NULL, base::Bind(&ConfigParserTest::CreateFakeURLFetcher,
                                 base::Unretained(this))) {
diff --git a/chrome/browser/safe_browsing/safe_browsing_database_unittest.cc b/chrome/browser/safe_browsing/safe_browsing_database_unittest.cc
index a99fde6..5eb5b0c 100644
--- a/chrome/browser/safe_browsing/safe_browsing_database_unittest.cc
+++ b/chrome/browser/safe_browsing/safe_browsing_database_unittest.cc
@@ -395,7 +395,7 @@ TEST_F(SafeBrowsingDatabaseTest, ListNameForBrowse) {
 
 TEST_F(SafeBrowsingDatabaseTest, ListNameForBrowseAndDownload) {
   database_.reset();
-  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop loop;
   SafeBrowsingStoreFile* browse_store = new SafeBrowsingStoreFile();
   SafeBrowsingStoreFile* download_store = new SafeBrowsingStoreFile();
   SafeBrowsingStoreFile* csd_whitelist_store = new SafeBrowsingStoreFile();
@@ -1123,7 +1123,7 @@ TEST_F(SafeBrowsingDatabaseTest, DISABLED_FileCorruptionHandling) {
   // influence task-posting.  Database specifically needs to the
   // file-backed.
   database_.reset();
-  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop loop;
   SafeBrowsingStoreFile* store = new SafeBrowsingStoreFile();
   database_.reset(new SafeBrowsingDatabaseNew(store, NULL, NULL, NULL, NULL,
                                               NULL, NULL));
@@ -1192,7 +1192,7 @@ TEST_F(SafeBrowsingDatabaseTest, DISABLED_FileCorruptionHandling) {
 // Checks database reading and writing.
 TEST_F(SafeBrowsingDatabaseTest, ContainsDownloadUrl) {
   database_.reset();
-  base::MessageLoop loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop loop;
   SafeBrowsingStoreFile* browse_store = new SafeBrowsingStoreFile();
   SafeBrowsingStoreFile* download_store = new SafeBrowsingStoreFile();
   SafeBrowsingStoreFile* csd_whitelist_store = new SafeBrowsingStoreFile();
diff --git a/chrome/browser/spellchecker/spellcheck_host_metrics_unittest.cc b/chrome/browser/spellchecker/spellcheck_host_metrics_unittest.cc
index bd434e5..2a00597 100644
--- a/chrome/browser/spellchecker/spellcheck_host_metrics_unittest.cc
+++ b/chrome/browser/spellchecker/spellcheck_host_metrics_unittest.cc
@@ -20,7 +20,7 @@
 
 class SpellcheckHostMetricsTest : public testing::Test {
  public:
-  SpellcheckHostMetricsTest() : loop_(base::MessageLoop::TYPE_DEFAULT) {
+  SpellcheckHostMetricsTest() {
   }
 
   static void SetUpTestCase() {
diff --git a/chrome/browser/sync_file_system/local/local_file_change_tracker_unittest.cc b/chrome/browser/sync_file_system/local/local_file_change_tracker_unittest.cc
index b7fe420..2171858 100644
--- a/chrome/browser/sync_file_system/local/local_file_change_tracker_unittest.cc
+++ b/chrome/browser/sync_file_system/local/local_file_change_tracker_unittest.cc
@@ -34,8 +34,7 @@ namespace sync_file_system {
 class LocalFileChangeTrackerTest : public testing::Test {
  public:
   LocalFileChangeTrackerTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        file_system_(GURL("http://example.com"),
+      : file_system_(GURL("http://example.com"),
                      base::MessageLoopProxy::current().get(),
                      base::MessageLoopProxy::current().get()) {}
 
@@ -106,7 +105,7 @@ class LocalFileChangeTrackerTest : public testing::Test {
   }
 
   ScopedEnableSyncFSDirectoryOperation enable_directory_operation_;
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   CannedSyncableFileSystem file_system_;
 
  private:
diff --git a/chrome/browser/themes/theme_syncable_service_unittest.cc b/chrome/browser/themes/theme_syncable_service_unittest.cc
index c1af3fb..42f6974 100644
--- a/chrome/browser/themes/theme_syncable_service_unittest.cc
+++ b/chrome/browser/themes/theme_syncable_service_unittest.cc
@@ -168,8 +168,7 @@ scoped_refptr<extensions::Extension> MakeThemeExtension(
 class ThemeSyncableServiceTest : public testing::Test {
  protected:
   ThemeSyncableServiceTest()
-      : loop_(base::MessageLoop::TYPE_DEFAULT),
-        ui_thread_(content::BrowserThread::UI, &loop_),
+      : ui_thread_(content::BrowserThread::UI, &loop_),
         file_thread_(content::BrowserThread::FILE, &loop_),
         fake_theme_service_(NULL) {}
 
diff --git a/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc b/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
index 9955011..3df3362 100644
--- a/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
+++ b/chrome/renderer/media/chrome_webrtc_log_message_delegate_unittest.cc
@@ -13,7 +13,7 @@
 TEST(ChromeWebRtcLogMessageDelegateTest, Basic) {
   const char kTestString[] = "abcdefghijklmnopqrstuvwxyz";
 
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   scoped_refptr<MockWebRtcLoggingMessageFilter> log_message_filter(
       new MockWebRtcLoggingMessageFilter(message_loop.message_loop_proxy()));
diff --git a/cloud_print/gcp20/prototype/gcp20_device.cc b/cloud_print/gcp20/prototype/gcp20_device.cc
index 57972a3..74040bd0 100644
--- a/cloud_print/gcp20/prototype/gcp20_device.cc
+++ b/cloud_print/gcp20/prototype/gcp20_device.cc
@@ -90,7 +90,7 @@ int main(int argc, char* argv[]) {
 
   signal(SIGINT, OnAbort);  // Handle Ctrl+C signal.
 
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   g_message_loop = &loop;
   g_message_loop->PostTask(FROM_HERE, base::Bind(&StartPrinter, &printer));
   base::RunLoop runner;
diff --git a/cloud_print/service/service_state.cc b/cloud_print/service/service_state.cc
index 01d315b..0894e20 100644
--- a/cloud_print/service/service_state.cc
+++ b/cloud_print/service/service_state.cc
@@ -160,7 +160,7 @@ std::string ServiceState::ToString() {
 std::string ServiceState::LoginToGoogle(const std::string& service,
                                         const std::string& email,
                                         const std::string& password) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
 
   net::URLRequestContextBuilder builder;
   scoped_ptr<net::URLRequestContext> context(builder.Build());
diff --git a/content/browser/appcache/chrome_appcache_service_unittest.cc b/content/browser/appcache/chrome_appcache_service_unittest.cc
index a4e895c..36d70c7 100644
--- a/content/browser/appcache/chrome_appcache_service_unittest.cc
+++ b/content/browser/appcache/chrome_appcache_service_unittest.cc
@@ -63,8 +63,7 @@ class MockURLRequestContextGetter : public net::URLRequestContextGetter {
 class ChromeAppCacheServiceTest : public testing::Test {
  public:
   ChromeAppCacheServiceTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        kProtectedManifestURL(kProtectedManifest),
+      : kProtectedManifestURL(kProtectedManifest),
         kNormalManifestURL(kNormalManifest),
         kSessionOnlyManifestURL(kSessionOnlyManifest),
         file_thread_(BrowserThread::FILE, &message_loop_),
@@ -79,7 +78,7 @@ class ChromeAppCacheServiceTest : public testing::Test {
       bool init_storage);
   void InsertDataIntoAppCache(ChromeAppCacheService* appcache_service);
 
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   base::ScopedTempDir temp_dir_;
   const GURL kProtectedManifestURL;
   const GURL kNormalManifestURL;
diff --git a/content/browser/indexed_db/indexed_db_unittest.cc b/content/browser/indexed_db/indexed_db_unittest.cc
index a028bba..c3704b8 100644
--- a/content/browser/indexed_db/indexed_db_unittest.cc
+++ b/content/browser/indexed_db/indexed_db_unittest.cc
@@ -30,7 +30,6 @@ class IndexedDBTest : public testing::Test {
   IndexedDBTest()
       : kNormalOrigin("http://normal/"),
         kSessionOnlyOrigin("http://session-only/"),
-        message_loop_(base::MessageLoop::TYPE_IO),
         task_runner_(new base::TestSimpleTaskRunner),
         special_storage_policy_(new quota::MockSpecialStoragePolicy),
         file_thread_(BrowserThread::FILE_USER_BLOCKING, &message_loop_),
@@ -41,7 +40,7 @@ class IndexedDBTest : public testing::Test {
  protected:
   void FlushIndexedDBTaskRunner() { task_runner_->RunUntilIdle(); }
 
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   scoped_refptr<base::TestSimpleTaskRunner> task_runner_;
   scoped_refptr<quota::MockSpecialStoragePolicy> special_storage_policy_;
 
diff --git a/content/browser/loader/resource_scheduler_unittest.cc b/content/browser/loader/resource_scheduler_unittest.cc
index 5f9c693..c0a58c0 100644
--- a/content/browser/loader/resource_scheduler_unittest.cc
+++ b/content/browser/loader/resource_scheduler_unittest.cc
@@ -125,7 +125,6 @@ class ResourceSchedulerTest : public testing::Test {
  protected:
   ResourceSchedulerTest()
       : next_request_id_(0),
-        message_loop_(base::MessageLoop::TYPE_IO),
         ui_thread_(BrowserThread::UI, &message_loop_),
         io_thread_(BrowserThread::IO, &message_loop_) {
     scheduler_.OnClientCreated(kChildId, kRouteId);
@@ -203,7 +202,7 @@ class ResourceSchedulerTest : public testing::Test {
   }
 
   int next_request_id_;
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   BrowserThreadImpl ui_thread_;
   BrowserThreadImpl io_thread_;
   ResourceDispatcherHostImpl rdh_;
diff --git a/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc b/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
index 76cb179..99e24e7 100644
--- a/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
+++ b/content/browser/renderer_host/media/audio_input_device_manager_unittest.cc
@@ -52,7 +52,7 @@ class AudioInputDeviceManagerTest : public testing::Test {
  protected:
   virtual void SetUp() OVERRIDE {
     // The test must run on Browser::IO.
-    message_loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+    message_loop_.reset(new base::MessageLoopForIO);
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
                                            message_loop_.get()));
     audio_manager_.reset(media::AudioManager::CreateForTesting());
diff --git a/content/browser/renderer_host/media/audio_mirroring_manager_unittest.cc b/content/browser/renderer_host/media/audio_mirroring_manager_unittest.cc
index 2468b2c..2ffd8974 100644
--- a/content/browser/renderer_host/media/audio_mirroring_manager_unittest.cc
+++ b/content/browser/renderer_host/media/audio_mirroring_manager_unittest.cc
@@ -46,8 +46,7 @@ class MockMirroringDestination
 class AudioMirroringManagerTest : public testing::Test {
  public:
   AudioMirroringManagerTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        io_thread_(BrowserThread::IO, &message_loop_),
+      : io_thread_(BrowserThread::IO, &message_loop_),
         params_(AudioParameters::AUDIO_FAKE, media::CHANNEL_LAYOUT_STEREO,
                 AudioParameters::kAudioCDSampleRate, 16,
                 AudioParameters::kAudioCDSampleRate / 10) {}
@@ -102,7 +101,7 @@ class AudioMirroringManagerTest : public testing::Test {
 }
 
  private:
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   BrowserThreadImpl io_thread_;
   AudioParameters params_;
   AudioMirroringManager mirroring_manager_;
diff --git a/content/browser/renderer_host/media/device_request_message_filter_unittest.cc b/content/browser/renderer_host/media/device_request_message_filter_unittest.cc
index 3a9382b..3628885 100644
--- a/content/browser/renderer_host/media/device_request_message_filter_unittest.cc
+++ b/content/browser/renderer_host/media/device_request_message_filter_unittest.cc
@@ -134,7 +134,7 @@ class DeviceRequestMessageFilterTest : public testing::Test {
   virtual ~DeviceRequestMessageFilterTest() {}
 
   virtual void SetUp() OVERRIDE {
-    message_loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+    message_loop_.reset(new base::MessageLoopForIO);
     io_thread_.reset(
         new TestBrowserThread(BrowserThread::IO, message_loop_.get()));
 
diff --git a/content/browser/renderer_host/media/media_stream_ui_controller_unittest.cc b/content/browser/renderer_host/media/media_stream_ui_controller_unittest.cc
index f65936e..048b078 100644
--- a/content/browser/renderer_host/media/media_stream_ui_controller_unittest.cc
+++ b/content/browser/renderer_host/media/media_stream_ui_controller_unittest.cc
@@ -43,7 +43,7 @@ class MediaStreamDeviceUIControllerTest
 
  protected:
   virtual void SetUp() {
-    message_loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+    message_loop_.reset(new base::MessageLoopForIO);
     ui_thread_.reset(new BrowserThreadImpl(BrowserThread::UI,
                                            message_loop_.get()));
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
diff --git a/content/browser/renderer_host/media/video_capture_manager_unittest.cc b/content/browser/renderer_host/media/video_capture_manager_unittest.cc
index 037498b..86d9e77 100644
--- a/content/browser/renderer_host/media/video_capture_manager_unittest.cc
+++ b/content/browser/renderer_host/media/video_capture_manager_unittest.cc
@@ -72,7 +72,7 @@ class VideoCaptureManagerTest : public testing::Test {
  protected:
   virtual void SetUp() OVERRIDE {
     listener_.reset(new MockMediaStreamProviderListener());
-    message_loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+    message_loop_.reset(new base::MessageLoopForIO);
     io_thread_.reset(new BrowserThreadImpl(BrowserThread::IO,
                                            message_loop_.get()));
     vcm_ = new VideoCaptureManager();
diff --git a/content/browser/resolve_proxy_msg_helper_unittest.cc b/content/browser/resolve_proxy_msg_helper_unittest.cc
index 91f0243..023fe43 100644
--- a/content/browser/resolve_proxy_msg_helper_unittest.cc
+++ b/content/browser/resolve_proxy_msg_helper_unittest.cc
@@ -63,7 +63,6 @@ class ResolveProxyMsgHelperTest : public testing::Test, public IPC::Listener {
         service_(
             new net::ProxyService(new MockProxyConfigService, resolver_, NULL)),
         helper_(new TestResolveProxyMsgHelper(service_.get(), this)),
-        message_loop_(base::MessageLoop::TYPE_IO),
         io_thread_(BrowserThread::IO, &message_loop_) {
     test_sink_.AddFilter(this);
   }
@@ -97,7 +96,7 @@ class ResolveProxyMsgHelperTest : public testing::Test, public IPC::Listener {
     return true;
   }
 
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   BrowserThreadImpl io_thread_;
   IPC::TestSink test_sink_;
 };
diff --git a/content/browser/streams/stream_url_request_job_unittest.cc b/content/browser/streams/stream_url_request_job_unittest.cc
index d337803..9caf684 100644
--- a/content/browser/streams/stream_url_request_job_unittest.cc
+++ b/content/browser/streams/stream_url_request_job_unittest.cc
@@ -51,7 +51,7 @@ class StreamURLRequestJobTest : public testing::Test {
     StreamRegistry* registry_;
   };
 
-  StreamURLRequestJobTest() : message_loop_(base::MessageLoop::TYPE_IO) {}
+  StreamURLRequestJobTest() {}
 
   virtual void SetUp() {
     registry_.reset(new StreamRegistry());
@@ -93,7 +93,7 @@ class StreamURLRequestJobTest : public testing::Test {
   }
 
  protected:
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   scoped_ptr<StreamRegistry> registry_;
 
   net::URLRequestContext url_request_context_;
diff --git a/content/child/resource_dispatcher_unittest.cc b/content/child/resource_dispatcher_unittest.cc
index 349ce8c..aef0a97 100644
--- a/content/child/resource_dispatcher_unittest.cc
+++ b/content/child/resource_dispatcher_unittest.cc
@@ -328,7 +328,7 @@ class DeferredResourceLoadingTest : public ResourceDispatcherTest,
 };
 
 TEST_F(DeferredResourceLoadingTest, DeferredLoadTest) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   ResourceLoaderBridge* bridge = CreateBridge();
 
diff --git a/content/ppapi_plugin/ppapi_broker_main.cc b/content/ppapi_plugin/ppapi_broker_main.cc
index b300c0f..78d0f1d 100644
--- a/content/ppapi_plugin/ppapi_broker_main.cc
+++ b/content/ppapi_plugin/ppapi_broker_main.cc
@@ -20,7 +20,7 @@ int PpapiBrokerMain(const MainFunctionParams& parameters) {
     ChildProcess::WaitForDebugger("PpapiBroker");
   }
 
-  base::MessageLoop main_message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop main_message_loop;
   base::PlatformThread::SetName("CrPPAPIBrokerMain");
   base::debug::TraceLog::GetInstance()->SetProcessName("PPAPI Broker Process");
   base::debug::TraceLog::GetInstance()->SetProcessSortIndex(
diff --git a/content/renderer/media/audio_message_filter_unittest.cc b/content/renderer/media/audio_message_filter_unittest.cc
index 46460dc..42bb9b3 100644
--- a/content/renderer/media/audio_message_filter_unittest.cc
+++ b/content/renderer/media/audio_message_filter_unittest.cc
@@ -71,7 +71,7 @@ class MockAudioDelegate : public media::AudioOutputIPCDelegate {
 }  // namespace
 
 TEST(AudioMessageFilterTest, Basic) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   scoped_refptr<AudioMessageFilter> filter(new AudioMessageFilter(
       message_loop.message_loop_proxy()));
@@ -118,7 +118,7 @@ TEST(AudioMessageFilterTest, Basic) {
 }
 
 TEST(AudioMessageFilterTest, Delegates) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   scoped_refptr<AudioMessageFilter> filter(new AudioMessageFilter(
       message_loop.message_loop_proxy()));
diff --git a/content/renderer/pepper/pepper_graphics_2d_host_unittest.cc b/content/renderer/pepper/pepper_graphics_2d_host_unittest.cc
index b17dfa7..e143aa7 100644
--- a/content/renderer/pepper/pepper_graphics_2d_host_unittest.cc
+++ b/content/renderer/pepper/pepper_graphics_2d_host_unittest.cc
@@ -30,9 +30,7 @@ class PepperGraphics2DHostTest : public testing::Test {
     return PepperGraphics2DHost::ConvertToLogicalPixels(scale, op_rect, delta);
   }
 
-  PepperGraphics2DHostTest()
-      : message_loop_(base::MessageLoop::TYPE_DEFAULT),
-        renderer_ppapi_host_(NULL, 12345) {}
+  PepperGraphics2DHostTest() : renderer_ppapi_host_(NULL, 12345) {}
 
   virtual ~PepperGraphics2DHostTest() {
     ppapi::ProxyAutoLock proxy_lock;
diff --git a/device/bluetooth/bluetooth_chromeos_unittest.cc b/device/bluetooth/bluetooth_chromeos_unittest.cc
index efc0b36..c49cee4 100644
--- a/device/bluetooth/bluetooth_chromeos_unittest.cc
+++ b/device/bluetooth/bluetooth_chromeos_unittest.cc
@@ -264,7 +264,7 @@ class BluetoothChromeOSTest : public testing::Test {
     ASSERT_TRUE(adapter_.get() != NULL);
 
     if (base::MessageLoop::current() == NULL) {
-      base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+      base::MessageLoop message_loop;
       DiscoverDevices();
       return;
     }
@@ -508,7 +508,7 @@ TEST_F(BluetoothChromeOSTest, BecomeNotPowered) {
 }
 
 TEST_F(BluetoothChromeOSTest, StopDiscovery) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
 
   GetAdapter();
 
@@ -551,7 +551,7 @@ TEST_F(BluetoothChromeOSTest, StopDiscovery) {
 }
 
 TEST_F(BluetoothChromeOSTest, StopDiscoveryAfterTwoStarts) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
 
   GetAdapter();
 
@@ -623,7 +623,7 @@ TEST_F(BluetoothChromeOSTest, StopDiscoveryAfterTwoStarts) {
 
 TEST_F(BluetoothChromeOSTest, Discovery) {
   // Test a simulated discovery session.
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
 
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
   GetAdapter();
@@ -670,7 +670,7 @@ TEST_F(BluetoothChromeOSTest, Discovery) {
 }
 
 TEST_F(BluetoothChromeOSTest, PoweredAndDiscovering) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
 
   GetAdapter();
   adapter_->SetPowered(
@@ -1169,7 +1169,7 @@ TEST_F(BluetoothChromeOSTest, DisconnectUnconnectedDevice) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairAppleMouse) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1230,7 +1230,7 @@ TEST_F(BluetoothChromeOSTest, PairAppleMouse) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairAppleKeyboard) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1292,7 +1292,7 @@ TEST_F(BluetoothChromeOSTest, PairAppleKeyboard) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairMotorolaKeyboard) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1375,7 +1375,7 @@ TEST_F(BluetoothChromeOSTest, PairMotorolaKeyboard) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairSonyHeadphones) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1438,7 +1438,7 @@ TEST_F(BluetoothChromeOSTest, PairSonyHeadphones) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairPhone) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1498,7 +1498,7 @@ TEST_F(BluetoothChromeOSTest, PairPhone) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairWeirdDevice) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1559,7 +1559,7 @@ TEST_F(BluetoothChromeOSTest, PairWeirdDevice) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairUnpairableDeviceFails) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1602,7 +1602,7 @@ TEST_F(BluetoothChromeOSTest, PairUnpairableDeviceFails) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingFails) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1646,7 +1646,7 @@ TEST_F(BluetoothChromeOSTest, PairingFails) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingFailsAtConnection) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1703,7 +1703,7 @@ TEST_F(BluetoothChromeOSTest, PairingFailsAtConnection) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingRejectedAtPinCode) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1750,7 +1750,7 @@ TEST_F(BluetoothChromeOSTest, PairingRejectedAtPinCode) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingCancelledAtPinCode) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1797,7 +1797,7 @@ TEST_F(BluetoothChromeOSTest, PairingCancelledAtPinCode) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingRejectedAtPasskey) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1844,7 +1844,7 @@ TEST_F(BluetoothChromeOSTest, PairingRejectedAtPasskey) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingCancelledAtPasskey) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1891,7 +1891,7 @@ TEST_F(BluetoothChromeOSTest, PairingCancelledAtPasskey) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingRejectedAtConfirmation) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1938,7 +1938,7 @@ TEST_F(BluetoothChromeOSTest, PairingRejectedAtConfirmation) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingCancelledAtConfirmation) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
@@ -1985,7 +1985,7 @@ TEST_F(BluetoothChromeOSTest, PairingCancelledAtConfirmation) {
 }
 
 TEST_F(BluetoothChromeOSTest, PairingCancelledInFlight) {
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   fake_bluetooth_device_client_->SetSimulationIntervalMs(10);
 
   GetAdapter();
diff --git a/device/bluetooth/bluetooth_profile_chromeos_unittest.cc b/device/bluetooth/bluetooth_profile_chromeos_unittest.cc
index 1792cda..dd7c945 100644
--- a/device/bluetooth/bluetooth_profile_chromeos_unittest.cc
+++ b/device/bluetooth/bluetooth_profile_chromeos_unittest.cc
@@ -31,8 +31,7 @@ namespace chromeos {
 class BluetoothProfileChromeOSTest : public testing::Test {
  public:
   BluetoothProfileChromeOSTest()
-      : message_loop_(base::MessageLoop::TYPE_IO),
-        callback_count_(0),
+      : callback_count_(0),
         error_callback_count_(0),
         profile_callback_count_(0),
         connection_callback_count_(0),
@@ -102,7 +101,7 @@ class BluetoothProfileChromeOSTest : public testing::Test {
   }
 
  protected:
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
 
   FakeBluetoothProfileManagerClient* fake_bluetooth_profile_manager_client_;
   scoped_refptr<BluetoothAdapter> adapter_;
diff --git a/gin/modules/timer_unittest.cc b/gin/modules/timer_unittest.cc
index aaffbde..98267475 100644
--- a/gin/modules/timer_unittest.cc
+++ b/gin/modules/timer_unittest.cc
@@ -57,8 +57,7 @@ struct TestHelper {
       : runner(new Runner(&delegate, isolate)),
         scope(runner.get()),
         timer_module(TimerModule::Create(isolate)),
-        result(Result::Create(isolate)),
-        loop(base::MessageLoop::TYPE_DEFAULT) {
+        result(Result::Create(isolate)) {
     EXPECT_FALSE(runner->global().IsEmpty());
     runner->global()->Set(StringToV8(isolate, "timer"),
                           timer_module->GetWrapper(isolate));
diff --git a/media/audio/audio_input_unittest.cc b/media/audio/audio_input_unittest.cc
index eb15b34..260598b 100644
--- a/media/audio/audio_input_unittest.cc
+++ b/media/audio/audio_input_unittest.cc
@@ -161,7 +161,7 @@ TEST(AudioInputTest, MAYBE_Record) {
   scoped_ptr<AudioManager> audio_man(AudioManager::CreateForTesting());
   if (!CanRunAudioTests(audio_man.get()))
     return;
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_DEFAULT);
+  base::MessageLoop message_loop;
   AudioInputStream* ais = CreateTestAudioInputStream(audio_man.get());
   EXPECT_TRUE(ais->Open());
 
diff --git a/media/base/user_input_monitor_unittest.cc b/media/base/user_input_monitor_unittest.cc
index 1afde601..55e6cca 100644
--- a/media/base/user_input_monitor_unittest.cc
+++ b/media/base/user_input_monitor_unittest.cc
@@ -47,7 +47,7 @@ TEST(UserInputMonitorTest, KeyPressCounter) {
 
 TEST(UserInputMonitorTest, CreatePlatformSpecific) {
 #if defined(OS_LINUX)
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 #else
   base::MessageLoopForUI message_loop;
 #endif  // defined(OS_LINUX)
diff --git a/net/disk_cache/stress_cache.cc b/net/disk_cache/stress_cache.cc
index 9c3c5a6..3b91c3b 100644
--- a/net/disk_cache/stress_cache.cc
+++ b/net/disk_cache/stress_cache.cc
@@ -279,7 +279,7 @@ int main(int argc, const char* argv[]) {
 
   // Some time for the memory manager to flush stuff.
   base::PlatformThread::Sleep(base::TimeDelta::FromSeconds(3));
-  base::MessageLoop message_loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO message_loop;
 
   char* end;
   long int iteration = strtol(argv[1], &end, 0);
diff --git a/net/test/embedded_test_server/embedded_test_server_unittest.cc b/net/test/embedded_test_server/embedded_test_server_unittest.cc
index a9c2efb..9823947 100644
--- a/net/test/embedded_test_server/embedded_test_server_unittest.cc
+++ b/net/test/embedded_test_server/embedded_test_server_unittest.cc
@@ -270,7 +270,7 @@ class EmbeddedTestServerThreadingTestDelegate
 
     scoped_ptr<base::MessageLoop> loop;
     if (message_loop_present_on_initialize_)
-      loop.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+      loop.reset(new base::MessageLoopForIO);
 
     // Create the test server instance.
     EmbeddedTestServer server;
@@ -280,7 +280,7 @@ class EmbeddedTestServerThreadingTestDelegate
 
     // Make a request and wait for the reply.
     if (!loop)
-      loop.reset(new base::MessageLoop(base::MessageLoop::TYPE_IO));
+      loop.reset(new base::MessageLoopForIO);
 
     scoped_ptr<URLFetcher> fetcher(URLFetcher::Create(
         server.GetURL("/test?q=foo"), URLFetcher::GET, this));
diff --git a/net/tools/dump_cache/dump_files.cc b/net/tools/dump_cache/dump_files.cc
index 7f4fb58..78b5d34 100644
--- a/net/tools/dump_cache/dump_files.cc
+++ b/net/tools/dump_cache/dump_files.cc
@@ -57,7 +57,7 @@ int GetMajorVersionFromFile(const base::FilePath& name) {
 // Dumps the contents of the Stats record.
 void DumpStats(const base::FilePath& path, disk_cache::CacheAddr addr) {
   // We need a message loop, although we really don't run any task.
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
 
   disk_cache::BlockFiles block_files(path);
   if (!block_files.Init(false)) {
@@ -355,7 +355,7 @@ int DumpContents(const base::FilePath& input_path) {
   DumpHeaders(input_path);
 
   // We need a message loop, although we really don't run any task.
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
   CacheDumper dumper(input_path);
   if (!dumper.Init())
     return -1;
diff --git a/net/tools/dump_cache/upgrade_win.cc b/net/tools/dump_cache/upgrade_win.cc
index 5135592..68744d3 100644
--- a/net/tools/dump_cache/upgrade_win.cc
+++ b/net/tools/dump_cache/upgrade_win.cc
@@ -893,7 +893,7 @@ HANDLE CreateServer(base::string16* pipe_number) {
 
 // This is the controller process for an upgrade operation.
 int UpgradeCache(const base::FilePath& output_path, HANDLE pipe) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
 
   MasterSM master(output_path, pipe);
   if (!master.DoInit()) {
@@ -908,7 +908,7 @@ int UpgradeCache(const base::FilePath& output_path, HANDLE pipe) {
 // This process will only execute commands from the controller.
 int RunSlave(const base::FilePath& input_path,
              const base::string16& pipe_number) {
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
 
   base::win::ScopedHandle pipe(OpenServer(pipe_number));
   if (!pipe.IsValid()) {
diff --git a/net/tools/fetch/fetch_client.cc b/net/tools/fetch/fetch_client.cc
index 8d4f5de..17d3b50 100644
--- a/net/tools/fetch/fetch_client.cc
+++ b/net/tools/fetch/fetch_client.cc
@@ -141,7 +141,7 @@ int main(int argc, char** argv) {
   bool use_cache = parsed_command_line.HasSwitch("use-cache");
 
   // Do work here.
-  base::MessageLoop loop(base::MessageLoop::TYPE_IO);
+  base::MessageLoopForIO loop;
 
   net::HttpStreamFactory::EnableNpnHttp2Draft04();
 
diff --git a/ppapi/proxy/ppb_message_loop_proxy.cc b/ppapi/proxy/ppb_message_loop_proxy.cc
index 582ddcb..2bc9694 100644
--- a/ppapi/proxy/ppb_message_loop_proxy.cc
+++ b/ppapi/proxy/ppb_message_loop_proxy.cc
@@ -86,7 +86,7 @@ int32_t MessageLoopResource::AttachToCurrentThread() {
   AddRef();
   slot->Set(this);
 
-  loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_DEFAULT));
+  loop_.reset(new base::MessageLoop);
   loop_proxy_ = base::MessageLoopProxy::current();
 
   // Post all pending work to the message loop.
diff --git a/ppapi/shared_impl/tracked_callback_unittest.cc b/ppapi/shared_impl/tracked_callback_unittest.cc
index 55db0aa..6a7376b 100644
--- a/ppapi/shared_impl/tracked_callback_unittest.cc
+++ b/ppapi/shared_impl/tracked_callback_unittest.cc
@@ -21,8 +21,7 @@ namespace {
 
 class TrackedCallbackTest : public testing::Test {
  public:
-  TrackedCallbackTest()
-      : message_loop_(base::MessageLoop::TYPE_DEFAULT), pp_instance_(1234) {}
+  TrackedCallbackTest() : pp_instance_(1234) {}
 
   PP_Instance pp_instance() const { return pp_instance_; }
 
diff --git a/remoting/host/daemon_process_unittest.cc b/remoting/host/daemon_process_unittest.cc
index 928b5b2..c0a9140 100644
--- a/remoting/host/daemon_process_unittest.cc
+++ b/remoting/host/daemon_process_unittest.cc
@@ -145,14 +145,13 @@ class DaemonProcessTest : public testing::Test {
   }
 
  protected:
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
 
   scoped_ptr<MockDaemonProcess> daemon_process_;
   int terminal_id_;
 };
 
-DaemonProcessTest::DaemonProcessTest()
-    : message_loop_(base::MessageLoop::TYPE_IO), terminal_id_(0) {
+DaemonProcessTest::DaemonProcessTest() : terminal_id_(0) {
 }
 
 DaemonProcessTest::~DaemonProcessTest() {
diff --git a/remoting/host/native_messaging/native_messaging_reader_unittest.cc b/remoting/host/native_messaging/native_messaging_reader_unittest.cc
index 26ed78d..35af8a2 100644
--- a/remoting/host/native_messaging/native_messaging_reader_unittest.cc
+++ b/remoting/host/native_messaging/native_messaging_reader_unittest.cc
@@ -46,12 +46,11 @@ class NativeMessagingReaderTest : public testing::Test {
  private:
   // MessageLoop declared here, since the NativeMessageReader ctor requires a
   // MessageLoop to have been created.
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   base::RunLoop run_loop_;
 };
 
-NativeMessagingReaderTest::NativeMessagingReaderTest()
-    : message_loop_(base::MessageLoop::TYPE_IO) {
+NativeMessagingReaderTest::NativeMessagingReaderTest() {
 }
 
 NativeMessagingReaderTest::~NativeMessagingReaderTest() {}
diff --git a/remoting/host/win/worker_process_launcher_unittest.cc b/remoting/host/win/worker_process_launcher_unittest.cc
index cd92b11..5503ab9 100644
--- a/remoting/host/win/worker_process_launcher_unittest.cc
+++ b/remoting/host/win/worker_process_launcher_unittest.cc
@@ -152,7 +152,7 @@ class WorkerProcessLauncherTest
  protected:
   void DoLaunchProcess();
 
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
   scoped_refptr<AutoThreadTaskRunner> task_runner_;
 
   // Receives messages sent to the worker process.
@@ -180,9 +180,7 @@ class WorkerProcessLauncherTest
   ScopedHandle worker_process_;
 };
 
-WorkerProcessLauncherTest::WorkerProcessLauncherTest()
-    : message_loop_(base::MessageLoop::TYPE_IO),
-      event_handler_(NULL) {
+WorkerProcessLauncherTest::WorkerProcessLauncherTest() : event_handler_(NULL) {
 }
 
 WorkerProcessLauncherTest::~WorkerProcessLauncherTest() {
diff --git a/tools/ipc_fuzzer/replay/replay_process.cc b/tools/ipc_fuzzer/replay/replay_process.cc
index cf969ad..b141cd0 100644
--- a/tools/ipc_fuzzer/replay/replay_process.cc
+++ b/tools/ipc_fuzzer/replay/replay_process.cc
@@ -18,8 +18,7 @@
 namespace ipc_fuzzer {
 
 ReplayProcess::ReplayProcess()
-    : main_loop_(base::MessageLoop::TYPE_DEFAULT),
-      io_thread_("Chrome_ChildIOThread"),
+    : io_thread_("Chrome_ChildIOThread"),
       shutdown_event_(true, false),
       message_index_(0) {
 }
diff --git a/ui/message_center/message_center_impl_unittest.cc b/ui/message_center/message_center_impl_unittest.cc
index e97c6f8..1e8ab41 100644
--- a/ui/message_center/message_center_impl_unittest.cc
+++ b/ui/message_center/message_center_impl_unittest.cc
@@ -29,7 +29,7 @@ class MessageCenterImplTest : public testing::Test,
   virtual void SetUp() OVERRIDE {
     MessageCenter::Initialize();
     message_center_ = MessageCenter::Get();
-    loop_.reset(new base::MessageLoop(base::MessageLoop::TYPE_DEFAULT));
+    loop_.reset(new base::MessageLoop);
     run_loop_.reset(new base::RunLoop());
     closure_ = run_loop_->QuitClosure();
   }