Add UMA for PurgeAndSuspend.

third_party/WebKit/Source/web/WebMemoryStatistics.cpp

+// Copyright 2016 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 "public/web/WebMemoryStatistics.h"
+
+#include "platform/heap/Heap.h"
+#include "wtf/allocator/Partitions.h"
+
+namespace blink {
+
+namespace {
+
+class LightPartitionStatsDumperImpl : public WTF::PartitionStatsDumper {
+ public:
+  LightPartitionStatsDumperImpl() : m_totalActiveBytes(0) {}
+
+  void partitionDumpTotals(
+      const char* partitionName,
+      const WTF::PartitionMemoryStats* memoryStats) override {
+    m_totalActiveBytes += memoryStats->totalActiveBytes;
+  }
+
+  void partitionsDumpBucketStats(
+      const char* partitionName,
+      const WTF::PartitionBucketMemoryStats*) override {}
+
+  size_t totalActiveBytes() const { return m_totalActiveBytes; }
+
+ private:
+  size_t m_totalActiveBytes;
+};
+
+}  // namespace
+
+WebMemoryStatistics WebMemoryStatistics::Get() {
+  LightPartitionStatsDumperImpl dumper;
+  WebMemoryStatistics statistics;
+
+  WTF::Partitions::dumpMemoryStats(true, &dumper);
+  statistics.partitionAllocTotalAllocatedBytes = dumper.totalActiveBytes();
+
+  statistics.blinkGCTotalAllocatedBytes =
+      ProcessHeap::totalAllocatedObjectSize() +
+      ProcessHeap::totalMarkedObjectSize();
+  return statistics;
+}
+
+}  // namespace blink