Use OnceCallback for Mojo binding connection error handlers.

mojo/public/cpp/bindings/lib/associated_interface_ptr_state.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.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_ASSOCIATED_INTERFACE_PTR_STATE_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_ASSOCIATED_INTERFACE_PTR_STATE_H_
 
 #include <stdint.h>
 
 #include <algorithm>  // For |std::swap()|.
@@ skipping 89 matching lines @@
     proxy_.reset();
     return AssociatedInterfacePtrInfo<Interface>(std::move(handle), version_);
   }
 
   bool is_bound() const { return !!endpoint_client_; }
 
   bool encountered_error() const {
     return endpoint_client_ ? endpoint_client_->encountered_error() : false;
   }
 
-  void set_connection_error_handler(const base::Closure& error_handler) {
+  void set_connection_error_handler(base::OnceClosure error_handler) {
     DCHECK(endpoint_client_);
-    endpoint_client_->set_connection_error_handler(error_handler);
+    endpoint_client_->set_connection_error_handler(std::move(error_handler));
   }
 
   void set_connection_error_with_reason_handler(
-      const ConnectionErrorWithReasonCallback& error_handler) {
+      ConnectionErrorWithReasonCallback error_handler) {
     DCHECK(endpoint_client_);
-    endpoint_client_->set_connection_error_with_reason_handler(error_handler);
+    endpoint_client_->set_connection_error_with_reason_handler(
+        std::move(error_handler));
   }
 
   // Returns true if bound and awaiting a response to a message.
   bool has_pending_callbacks() const {
     return endpoint_client_ && endpoint_client_->has_pending_responders();
   }
 
   AssociatedGroup* associated_group() {
     return endpoint_client_ ? endpoint_client_->associated_group() : nullptr;
   }
@@ skipping 19 matching lines @@
 
   uint32_t version_;
 
   DISALLOW_COPY_AND_ASSIGN(AssociatedInterfacePtrState);
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_ASSOCIATED_INTERFACE_PTR_STATE_H_