[Tracing] Enable heap dumps with both type info and backtraces

content/child/web_memory_dump_provider_adapter.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 "content/child/web_memory_dump_provider_adapter.h"
 
+#include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
 #include "base/synchronization/lock.h"
 #include "base/trace_event/heap_profiler_allocation_context.h"
 #include "base/trace_event/heap_profiler_allocation_context_tracker.h"
 #include "base/trace_event/heap_profiler_allocation_register.h"
 #include "base/trace_event/heap_profiler_heap_dump_writer.h"
 #include "base/trace_event/process_memory_dump.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "base/trace_event/trace_event_memory_overhead.h"
 #include "content/child/web_process_memory_dump_impl.h"
@@ skipping 53 matching lines @@
       break;
     default:
       NOTREACHED();
       return false;
   }
   WebProcessMemoryDumpImpl web_pmd_impl(args.level_of_detail, pmd);
 
   if (args.level_of_detail == MemoryDumpLevelOfDetail::DETAILED &&
       web_memory_dump_provider_->supportsHeapProfiling() &&
       g_heap_profiling_enabled) {
-    HeapDumpWriter writer(pmd->session_state()->stack_frame_deduplicator(),
-                          pmd->session_state()->type_name_deduplicator());
     TraceEventMemoryOverhead overhead;
-
+    hash_map<AllocationContext, size_t> bytes_by_context;
     {
       AutoLock lock(g_allocation_register_lock.Get());
       for (const auto& alloc_size : *g_allocation_register)
-        writer.InsertAllocation(alloc_size.context, alloc_size.size);
+        bytes_by_context[alloc_size.context] += alloc_size.size;
 
       g_allocation_register->EstimateTraceMemoryOverhead(&overhead);
     }
 
-    pmd->AddHeapDump("partition_alloc", writer.WriteHeapDump());
+    scoped_refptr<TracedValue> heap_dump = ExportHeapDump(
+        bytes_by_context, pmd->session_state()->stack_frame_deduplicator(),
+        pmd->session_state()->type_name_deduplicator());
+    pmd->AddHeapDump("partition_alloc", heap_dump);
     overhead.DumpInto("tracing/heap_profiler", pmd);
   }
 
   return web_memory_dump_provider_->onMemoryDump(level, &web_pmd_impl);
 }
 
 void WebMemoryDumpProviderAdapter::OnHeapProfilingEnabled(bool enabled) {
   if (!web_memory_dump_provider_->supportsHeapProfiling())
     return;
 
@@ skipping 15 matching lines @@
     web_memory_dump_provider_->onHeapProfilingEnabled(ReportAllocation,
                                                       ReportFree);
   } else {
     web_memory_dump_provider_->onHeapProfilingEnabled(nullptr, nullptr);
   }
 
   g_heap_profiling_enabled = enabled;
 }
 
 }  // namespace content