[tracing] Introduce support for userland memory allocators dumps.

base/trace_event/memory_allocator_dump.h

Index: base/trace_event/memory_allocator_dump.h
diff --git a/base/trace_event/memory_allocator_dump.h b/base/trace_event/memory_allocator_dump.h
new file mode 100644
index 0000000000000000000000000000000000000000..4d7293e710f5ef19f591ae4cdb8d3b712a3ac3f0
--- /dev/null
+++ b/base/trace_event/memory_allocator_dump.h
@@ -0,0 +1,66 @@
+// 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_MEMORY_ALLOCATOR_DUMP_H_
+#define BASE_TRACE_EVENT_MEMORY_ALLOCATOR_DUMP_H_
+
+#include "base/base_export.h"
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/trace_event/memory_allocator_attributes.h"
+#include "base/values.h"
+
+namespace base {
+namespace trace_event {
+
+class MemoryDumpManager;
+class TracedValue;
+
+// Data model for user-land memory allocator dumps.
+class BASE_EXPORT MemoryAllocatorDump {
+ public:
+  MemoryAllocatorDump(const std::string& name, MemoryAllocatorDump* parent);
+  ~MemoryAllocatorDump();
+
+  const std::string& name() const { return name_; }
+  const MemoryAllocatorDump* parent() const { return parent_; }
+
+  void set_physical_size_in_bytes(uint64 value) {
+    physical_size_in_bytes_ = value;
+  }
+  uint64 physical_size_in_bytes() const { return physical_size_in_bytes_; }
+
+  void set_allocated_objects_count(uint64 value) {
+    allocated_objects_count_ = value;
+  }
+  uint64 allocated_objects_count() const { return allocated_objects_count_; }
+
+  void set_allocated_objects_size_in_bytes(uint64 value) {
+    allocated_objects_size_in_bytes_ = value;
+  }
+  uint64 allocated_objects_size_in_bytes() const {
+    return allocated_objects_size_in_bytes_;
+  }
+
+  void SetExtraAttribute(const std::string& name, int value);
+  int GetExtraIntegerAttribute(const std::string& name) const;
+
+  // Called at trace generation time to populate the TracedValue.
+  void AsValueInto(TracedValue* value) const;
+
+ private:
+  const std::string name_;
+  MemoryAllocatorDump* const parent_;  // Not owned.
+  uint64 physical_size_in_bytes_;
+  uint64 allocated_objects_count_;
+  uint64 allocated_objects_size_in_bytes_;
+  DictionaryValue extra_attributes_;
+
+  DISALLOW_COPY_AND_ASSIGN(MemoryAllocatorDump);
+};
+
+}  // namespace trace_event
+}  // namespace base
+
+#endif  // BASE_TRACE_EVENT_MEMORY_ALLOCATOR_DUMP_H_