Revert of [tracing] Dump child processes' memory metrics in browser

base/trace_event/process_memory_maps_dump_provider.h

Index: base/trace_event/process_memory_maps_dump_provider.h
diff --git a/base/trace_event/process_memory_maps_dump_provider.h b/base/trace_event/process_memory_maps_dump_provider.h
new file mode 100644
index 0000000000000000000000000000000000000000..84badfe9a06070697867cbd1ca434d9a907071a9
--- /dev/null
+++ b/base/trace_event/process_memory_maps_dump_provider.h
@@ -0,0 +1,43 @@
+// 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_MAPS_DUMP_PROVIDER_H_
+#define BASE_TRACE_EVENT_PROCESS_MEMORY_MAPS_DUMP_PROVIDER_H_
+
+#include "base/gtest_prod_util.h"
+#include "base/macros.h"
+#include "base/memory/singleton.h"
+#include "base/trace_event/memory_dump_provider.h"
+#include "build/build_config.h"
+
+namespace base {
+namespace trace_event {
+
+// Dump provider which collects process-wide memory stats.
+class BASE_EXPORT ProcessMemoryMapsDumpProvider : public MemoryDumpProvider {
+ public:
+  static ProcessMemoryMapsDumpProvider* GetInstance();
+
+  // MemoryDumpProvider implementation.
+  bool OnMemoryDump(const MemoryDumpArgs& args,
+                    ProcessMemoryDump* pmd) override;
+
+ private:
+  friend struct DefaultSingletonTraits<ProcessMemoryMapsDumpProvider>;
+  FRIEND_TEST_ALL_PREFIXES(ProcessMemoryMapsDumpProviderTest, ParseProcSmaps);
+
+#if defined(OS_LINUX) || defined(OS_ANDROID) || defined(OS_NACL)
+  static FILE* proc_smaps_for_testing;
+#endif
+
+  ProcessMemoryMapsDumpProvider();
+  ~ProcessMemoryMapsDumpProvider() override;
+
+  DISALLOW_COPY_AND_ASSIGN(ProcessMemoryMapsDumpProvider);
+};
+
+}  // namespace trace_event
+}  // namespace base
+
+#endif  // BASE_TRACE_EVENT_PROCESS_MEMORY_MAPS_DUMP_PROVIDER_H_