Teach input_handler_proxy about once callbacks.

ui/events/blink/event_with_callback.cc

 // Copyright 2016 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/blink/event_with_callback.h"
 
 #include "base/memory/ptr_util.h"
 #include "ui/events/blink/blink_event_util.h"
 #include "ui/events/blink/did_overscroll_params.h"
 #include "ui/events/blink/web_input_event_traits.h"
 
 using blink::WebInputEvent;
 using blink::WebGestureEvent;
 
 namespace ui {
 
 EventWithCallback::EventWithCallback(
     WebScopedInputEvent event,
     const LatencyInfo& latency,
     base::TimeTicks timestamp_now,
-    const InputHandlerProxy::EventDispositionCallback& callback)
+    InputHandlerProxy::EventDispositionCallback callback)
     : event_(WebInputEventTraits::Clone(*event)),
       latency_(latency),
       creation_timestamp_(timestamp_now),
       last_coalesced_timestamp_(timestamp_now) {
-  original_events_.emplace_back(std::move(event), callback);
+  original_events_.emplace_back(std::move(event), std::move(callback));
 }
 
 EventWithCallback::EventWithCallback(
     WebScopedInputEvent event,
     const LatencyInfo& latency,
     base::TimeTicks creation_timestamp,
     base::TimeTicks last_coalesced_timestamp,
     std::unique_ptr<OriginalEventList> original_events)
     : event_(std::move(event)),
       latency_(latency),
@@ skipping 34 matching lines @@
 void EventWithCallback::RunCallbacks(
     InputHandlerProxy::EventDisposition disposition,
     const LatencyInfo& latency,
     std::unique_ptr<DidOverscrollParams> did_overscroll_params) {
   for (auto& original_event : original_events_) {
     std::unique_ptr<DidOverscrollParams> did_overscroll_params_copy;
     if (did_overscroll_params) {
       did_overscroll_params_copy =
           base::MakeUnique<DidOverscrollParams>(*did_overscroll_params);
     }
-    original_event.callback_.Run(disposition, std::move(original_event.event_),
-                                 latency, std::move(did_overscroll_params));
+    std::move(original_event.callback_)
+        .Run(disposition, std::move(original_event.event_), latency,
+             std::move(did_overscroll_params));
   }
 }
 
 EventWithCallback::OriginalEventWithCallback::OriginalEventWithCallback(
     WebScopedInputEvent event,
-    const InputHandlerProxy::EventDispositionCallback& callback)
-    : event_(std::move(event)), callback_(callback) {}
+    InputHandlerProxy::EventDispositionCallback callback)
+    : event_(std::move(event)), callback_(std::move(callback)) {}
 
 EventWithCallback::OriginalEventWithCallback::~OriginalEventWithCallback() {}
 
 }  // namespace ui