[Memory UMA] Return a memory summary struct with the ack message

base/trace_event/memory_dump_request_args.cc

 // 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.
 
 #include "base/trace_event/memory_dump_request_args.h"
 
 #include "base/logging.h"
 
 namespace base {
 namespace trace_event {
@@ skipping 44 matching lines @@
   if (str == "light")
     return MemoryDumpLevelOfDetail::LIGHT;
   if (str == "detailed")
     return MemoryDumpLevelOfDetail::DETAILED;
   NOTREACHED();
   return MemoryDumpLevelOfDetail::LAST;
 }
 
 MemoryDumpCallbackResult::MemoryDumpCallbackResult() {}
 
+MemoryDumpCallbackResult::MemoryDumpCallbackResult(
+    const MemoryDumpCallbackResult&) = default;
+
 MemoryDumpCallbackResult::~MemoryDumpCallbackResult() {}
 
 }  // namespace trace_event
 }  // namespace base