Make Dispatcher::Type an enum class.

mojo/edk/system/platform_handle_dispatcher_unittest.cc

Index: mojo/edk/system/platform_handle_dispatcher_unittest.cc
diff --git a/mojo/edk/system/platform_handle_dispatcher_unittest.cc b/mojo/edk/system/platform_handle_dispatcher_unittest.cc
index dae53b43dd6225a35455d8b0fd74fbc4244d3bb0..3b37b721723472d3b7f4e6ef03f0c89f95110871 100644
--- a/mojo/edk/system/platform_handle_dispatcher_unittest.cc
+++ b/mojo/edk/system/platform_handle_dispatcher_unittest.cc
@@ -39,7 +39,7 @@ TEST(PlatformHandleDispatcherTest, Basic) {
   scoped_refptr<PlatformHandleDispatcher> dispatcher(
       new PlatformHandleDispatcher(h.Pass()));
   EXPECT_FALSE(h.is_valid());
-  EXPECT_EQ(Dispatcher::kTypePlatformHandle, dispatcher->GetType());
+  EXPECT_EQ(Dispatcher::Type::PLATFORM_HANDLE, dispatcher->GetType());
 
   h = dispatcher->PassPlatformHandle().Pass();
   EXPECT_TRUE(h.is_valid());
@@ -79,7 +79,7 @@ TEST(PlatformHandleDispatcherTest, CreateEquivalentDispatcherAndClose) {
   DispatcherTransport transport(
       test::DispatcherTryStartTransport(dispatcher.get()));
   EXPECT_TRUE(transport.is_valid());
-  EXPECT_EQ(Dispatcher::kTypePlatformHandle, transport.GetType());
+  EXPECT_EQ(Dispatcher::Type::PLATFORM_HANDLE, transport.GetType());
   EXPECT_FALSE(transport.IsBusy());
 
   scoped_refptr<Dispatcher> generic_dispatcher =
@@ -90,7 +90,7 @@ TEST(PlatformHandleDispatcherTest, CreateEquivalentDispatcherAndClose) {
   EXPECT_TRUE(dispatcher->HasOneRef());
   dispatcher = nullptr;
 
-  ASSERT_EQ(Dispatcher::kTypePlatformHandle, generic_dispatcher->GetType());
+  ASSERT_EQ(Dispatcher::Type::PLATFORM_HANDLE, generic_dispatcher->GetType());
   dispatcher = static_cast<PlatformHandleDispatcher*>(generic_dispatcher.get());
 
   fp = mojo::test::FILEFromPlatformHandle(dispatcher->PassPlatformHandle(),