[tracing] Add sqlite memory statistics to tracing.

sql/process_memory_dump_provider.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 SQL_PROCESS_MEMORY_DUMP_PROVIDER_H
+#define SQL_PROCESS_MEMORY_DUMP_PROVIDER_H
+
+#include "base/memory/singleton.h"
+#include "base/trace_event/memory_dump_provider.h"
+#include "sql/sql_export.h"
+
+namespace sql {
+
+class SQL_EXPORT ProcessMemoryDumpProvider

[Primiano Tucci (use gerrit), 2015/09/30 10:26:56]

Can you please add a comment explaining what this is dumping? HOw is that
different from the per-connection MDP ?

[ssid, 2015/10/02 17:06:10]

Done.

+    : public base::trace_event::MemoryDumpProvider {
+ public:
+  static ProcessMemoryDumpProvider* GetInstance();
+
+  // MemoryDumpProvider implementation.
+  bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
+                    base::trace_event::ProcessMemoryDump* pmd) override;
+
+ private:
+  friend struct DefaultSingletonTraits<ProcessMemoryDumpProvider>;
+
+  ProcessMemoryDumpProvider();
+  ~ProcessMemoryDumpProvider() override;
+
+  DISALLOW_COPY_AND_ASSIGN(ProcessMemoryDumpProvider);
+};
+
+}  // namespace sql
+
+#endif  // SQL_PROCESS_MEMORY_DUMP_PROVIDER_H