[tracing] Switch to new heap dump format.

third_party/WebKit/Source/platform/heap/BlinkGCMemoryDumpProvider.cpp

 // 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 "platform/heap/BlinkGCMemoryDumpProvider.h"
 
 #include "base/trace_event/heap_profiler_allocation_context_tracker.h"
 #include "base/trace_event/heap_profiler_allocation_register.h"
 #include "base/trace_event/memory_allocator_dump.h"
 #include "base/trace_event/process_memory_dump.h"
@@ skipping 46 matching lines @@
   MemoryDumpLevelOfDetail levelOfDetail = args.level_of_detail;
   // In the case of a detailed dump perform a mark-only GC pass to collect
   // more detailed stats.
   if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED)
     ThreadState::current()->collectGarbage(BlinkGC::NoHeapPointersOnStack,
                                            BlinkGC::TakeSnapshot,
                                            BlinkGC::ForcedGC);
   dumpMemoryTotals(memoryDump);
 
   if (m_isHeapProfilingEnabled) {
-    // Overhead should always be reported, regardless of light vs. heavy.
-    base::trace_event::TraceEventMemoryOverhead overhead;
-    base::hash_map<base::trace_event::AllocationContext,
-                   base::trace_event::AllocationMetrics>
-        metricsByContext;
-    {
-      MutexLocker locker(m_allocationRegisterMutex);
-      if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED) {
-        for (const auto& allocSize : *m_allocationRegister) {
-          base::trace_event::AllocationMetrics& metrics =
-              metricsByContext[allocSize.context];
-          metrics.size += allocSize.size;
-          metrics.count++;
-        }
-      }
-      m_allocationRegister->EstimateTraceMemoryOverhead(&overhead);
-    }
-    memoryDump->DumpHeapUsage(metricsByContext, overhead, "blink_gc");
+    MutexLocker locker(m_allocationRegisterMutex);
+    memoryDump->DumpHeapUsage(*m_allocationRegister, "blink_gc");
   }
 
   // Merge all dumps collected by ThreadHeap::collectGarbage.
   if (levelOfDetail == MemoryDumpLevelOfDetail::DETAILED)
     memoryDump->TakeAllDumpsFrom(m_currentProcessMemoryDump.get());
   return true;
 }
 
 void BlinkGCMemoryDumpProvider::OnHeapProfilingEnabled(bool enabled) {
   if (enabled) {
@@ skipping 43 matching lines @@
     m_allocationRegister->Insert(address, size, context);
 }
 
 void BlinkGCMemoryDumpProvider::remove(Address address) {
   MutexLocker locker(m_allocationRegisterMutex);
   if (m_allocationRegister)
     m_allocationRegister->Remove(address);
 }
 
 }  // namespace blink