[tracing] Improve the memory maps dumper generation format.

base/trace_event/process_memory_totals.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 BASE_TRACE_EVENT_PROCESS_MEMORY_TOTALS_H_
 #define BASE_TRACE_EVENT_PROCESS_MEMORY_TOTALS_H_
 
 #include "base/base_export.h"
 #include "base/basictypes.h"
 
 namespace base {
 namespace trace_event {
 
 class TracedValue;
 
-// Dump provider which collects process-wide memory stats.
+// Data model for process-wide memory stats.
 class BASE_EXPORT ProcessMemoryTotals {
  public:
   ProcessMemoryTotals() : resident_set_bytes_(0) {}
 
   // Called at trace generation time to populate the TracedValue.
   void AsValueInto(TracedValue* value) const;
 
   uint64 resident_set_bytes() const { return resident_set_bytes_; }
   void set_resident_set_bytes(uint64 value) { resident_set_bytes_ = value; }
 
  private:
   uint64 resident_set_bytes_;
 
   DISALLOW_COPY_AND_ASSIGN(ProcessMemoryTotals);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_PROCESS_MEMORY_TOTALS_H_