Remove calls to deprecated MessageLoop methods on Windows and Linux.

ui/events/platform/platform_event_source_unittest.cc

 // Copyright 2014 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 "ui/events/platform/platform_event_source.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 484 matching lines @@
 // Provides mechanism for running tests from inside an active message-loop.
 class PlatformEventTestWithMessageLoop : public PlatformEventTest {
  public:
   PlatformEventTestWithMessageLoop() {}
   ~PlatformEventTestWithMessageLoop() override {}
 
   void Run() {
     message_loop_.task_runner()->PostTask(
         FROM_HERE, base::Bind(&PlatformEventTestWithMessageLoop::RunTest,
                               base::Unretained(this)));
-    message_loop_.Run();
+    base::RunLoop().Run();
   }
 
  protected:
   void RunTest() {
     RunTestImpl();
     message_loop_.QuitWhenIdle();
   }
 
   virtual void RunTestImpl() = 0;
 
@@ skipping 255 matching lines @@
     ASSERT_EQ(2u, list.size());
     EXPECT_EQ(15, list[0]);
     EXPECT_EQ(10, list[1]);
   }
 };
 
 RUN_TEST_IN_MESSAGE_LOOP(
     ConsecutiveOverriddenDispatcherInTheSameMessageLoopIteration)
 
 }  // namespace ui