profiling: Allow to shut down client.

Change-Id: Iee28321d413402824ee00242cb4c776784061741
diff --git a/src/profiling/memory/client.h b/src/profiling/memory/client.h
index c9cb8b0..c9595c2 100644
--- a/src/profiling/memory/client.h
+++ b/src/profiling/memory/client.h
@@ -37,8 +37,11 @@
   SocketPool(std::vector<base::ScopedFile> sockets);
 
   BorrowedSocket Borrow();
+  void Shutdown();
 
  private:
+  bool shutdown_ = false;
+
   void Return(base::ScopedFile fd);
   std::mutex mutex_;
   std::condition_variable cv_;
@@ -136,6 +139,7 @@
                         uint64_t alloc_address,
                         void* (*unhooked_malloc)(size_t),
                         void (*unhooked_free)(void*));
+  void Shutdown();
 
   ClientConfiguration client_config_for_testing() { return client_config_; }