Update from https://crrev.com/318214

base/trace_event/process_memory_maps.cc

+// 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.
+
+#include "base/trace_event/process_memory_maps.h"
+
+#include "base/trace_event/trace_event_argument.h"
+
+namespace base {
+namespace trace_event {
+
+// static
+const uint32 ProcessMemoryMaps::VMRegion::kProtectionFlagsRead = 4;
+const uint32 ProcessMemoryMaps::VMRegion::kProtectionFlagsWrite = 2;
+const uint32 ProcessMemoryMaps::VMRegion::kProtectionFlagsExec = 1;
+
+ProcessMemoryMaps::ProcessMemoryMaps() {
+}
+
+ProcessMemoryMaps::~ProcessMemoryMaps() {
+}
+
+void ProcessMemoryMaps::AsValueInto(TracedValue* value) const {
+  value->BeginArray("vm_regions");
+  for (const auto& region : vm_regions_) {
+    value->BeginDictionary();
+
+    value->SetDouble("start_address", region.start_address);
+    value->SetDouble("size_in_bytes", region.size_in_bytes);
+    value->SetInteger("protection_flags", region.protection_flags);
+    value->SetString("mapped_file", region.mapped_file);
+    value->SetDouble("mapped_file_offset", region.mapped_file_offset);
+
+    value->BeginDictionary("byte_stats");
+    value->SetDouble("resident", region.byte_stats_resident);
+    value->SetDouble("anonymous", region.byte_stats_anonymous);
+    value->EndDictionary();
+
+    value->EndDictionary();
+  }
+  value->EndArray();
+}
+
+}  // namespace trace_event
+}  // namespace base