memory-infra: Remove is_enabled_ from MDM

base/trace_event/memory_tracing_observer.h

 // Copyright 2017 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_MEMORY_TRACING_OBSERVER_H_
 #define BASE_TRACE_EVENT_MEMORY_TRACING_OBSERVER_H_
 
 #include "base/macros.h"
 #include "base/trace_event/memory_dump_manager.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 14 matching lines @@
   ~MemoryTracingObserver() override;
 
   // TraceLog::EnabledStateObserver implementation.
   void OnTraceLogEnabled() override;
   void OnTraceLogDisabled() override;
 
   bool AddDumpToTraceIfEnabled(const MemoryDumpRequestArgs*,
                                const ProcessId,
                                const ProcessMemoryDump*);
 
+  bool IsMemoryInfraTracingEnabled();

[Primiano Tucci (use gerrit), 2017/04/28 15:58:17]

I think we don't need this, given the comment above

[ssid, 2017/04/28 18:35:04]

Yes!! :)

+
  private:
   MemoryDumpManager* const memory_dump_manager_;
   TraceLog* const trace_log_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryTracingObserver);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_MEMORY_TRACING_OBSERVER_H_