Fix declspec and GNU attribute order

mojo/edk/system/mutex.h

 // Copyright 2015 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.
 
 // A mutex class, with support for thread annotations.
 //
 // TODO(vtl): Currently, this is a fork of Chromium's
 // base/synchronization/lock.h (with names changed and minor modifications; it
 // still cheats and uses Chromium's lock_impl.*), but eventually we'll want our
 // own and, e.g., add support for non-exclusive (reader) locks.
 
 #ifndef MOJO_EDK_SYSTEM_MUTEX_H_
 #define MOJO_EDK_SYSTEM_MUTEX_H_
 
 #include "base/synchronization/lock_impl.h"
 #include "base/threading/platform_thread.h"
 #include "mojo/edk/system/system_impl_export.h"
 #include "mojo/edk/system/thread_annotations.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace mojo {
 namespace system {
 
 // Mutex -----------------------------------------------------------------------
 
-class MOJO_SYSTEM_IMPL_EXPORT MOJO_LOCKABLE Mutex {
+class MOJO_LOCKABLE MOJO_SYSTEM_IMPL_EXPORT Mutex {
  public:
 #if defined(NDEBUG) && !defined(DCHECK_ALWAYS_ON)
   Mutex() : lock_() {}
   ~Mutex() {}
 
   void Lock() MOJO_EXCLUSIVE_LOCK_FUNCTION() { lock_.Lock(); }
   void Unlock() MOJO_UNLOCK_FUNCTION() { lock_.Unlock(); }
 
   bool TryLock() MOJO_EXCLUSIVE_TRYLOCK_FUNCTION(true) { return lock_.Try(); }
 
@@ skipping 29 matching lines @@
   base::PlatformThreadRef owning_thread_ref_;
 #endif  // !NDEBUG || DCHECK_ALWAYS_ON
 
   base::internal::LockImpl lock_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(Mutex);
 };
 
 // MutexLocker -----------------------------------------------------------------
 
-class MOJO_SYSTEM_IMPL_EXPORT MOJO_SCOPED_LOCKABLE MutexLocker {
+class MOJO_SCOPED_LOCKABLE MOJO_SYSTEM_IMPL_EXPORT MutexLocker {
  public:
   explicit MutexLocker(Mutex* mutex) MOJO_EXCLUSIVE_LOCK_FUNCTION(mutex)
       : mutex_(mutex) {
     this->mutex_->Lock();
   }
   ~MutexLocker() MOJO_UNLOCK_FUNCTION() { this->mutex_->Unlock(); }
 
  private:
   Mutex* const mutex_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(MutexLocker);
 };
 
 }  // namespace system
 }  // namespace mojo
 
 #endif  // MOJO_EDK_SYSTEM_MUTEX_H_