[tracing] Simplify the MemoryAllocatorDump API

base/trace_event/malloc_dump_provider.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/malloc_dump_provider.h"
 
 #include <malloc.h>
 
 #include "base/trace_event/process_memory_dump.h"
 
@@ skipping 11 matching lines @@
 
 MallocDumpProvider::~MallocDumpProvider() {
 }
 
 // Called at trace dump point time. Creates a snapshot the memory counters for
 // the current process.
 bool MallocDumpProvider::OnMemoryDump(ProcessMemoryDump* pmd) {
   struct mallinfo info = mallinfo();
   DCHECK_GE(info.arena + info.hblkhd, info.uordblks);
 
-  MemoryAllocatorDump* dump =
-      pmd->CreateAllocatorDump("malloc", MemoryAllocatorDump::kRootHeap);
+  MemoryAllocatorDump* dump = pmd->CreateAllocatorDump("malloc");
   if (!dump)
     return false;
 
   // When the system allocator is implemented by tcmalloc, the total physical
   // size is given by |arena| and |hblkhd| is 0. In case of Android's jemalloc
   // |arena| is 0 and the outer pages size is reported by |hblkhd|. In case of
   // dlmalloc the total is given by |arena| + |hblkhd|.
   // For more details see link: http://goo.gl/fMR8lF.
-  dump->set_physical_size_in_bytes(info.arena + info.hblkhd);
-
-  // mallinfo doesn't support any allocated object count.
-  dump->set_allocated_objects_count(0);
+  dump->AddScalar(MemoryAllocatorDump::kNameOuterSize,
+                  MemoryAllocatorDump::kUnitsBytes, info.arena + info.hblkhd);
 
   // Total allocated space is given by |uordblks|.
-  dump->set_allocated_objects_size_in_bytes(info.uordblks);
+  dump->AddScalar(MemoryAllocatorDump::kNameInnerSize,
+                  MemoryAllocatorDump::kUnitsBytes, info.uordblks);
 
   return true;
 }
 
 }  // namespace trace_event
 }  // namespace base