[WIP] Add SharedMemoryTracker to dump base::SharedMemory usage

gpu/command_buffer/client/gles2_implementation.cc

Index: gpu/command_buffer/client/gles2_implementation.cc
diff --git a/gpu/command_buffer/client/gles2_implementation.cc b/gpu/command_buffer/client/gles2_implementation.cc
index fde1339e7f578cf12ab79fbbca90c78acff92b50..250f4d70979449e59dc0cc6b2e9ff037f8d26471 100644
--- a/gpu/command_buffer/client/gles2_implementation.cc
+++ b/gpu/command_buffer/client/gles2_implementation.cc
@@ -20,6 +20,7 @@
 #include "base/atomic_sequence_num.h"
 #include "base/bits.h"
 #include "base/compiler_specific.h"
+#include "base/memory/shared_memory_tracker.h"
 #include "base/numerics/safe_math.h"
 #include "base/strings/string_split.h"
 #include "base/strings/stringprintf.h"
@@ -442,10 +443,6 @@ bool GLES2Implementation::OnMemoryDump(
   if (!transfer_buffer_->HaveBuffer())
     return true;
 
-  const uint64_t tracing_process_id =
-      base::trace_event::MemoryDumpManager::GetInstance()
-          ->GetTracingProcessId();
-
   MemoryAllocatorDump* dump = pmd->CreateAllocatorDump(base::StringPrintf(
       "gpu/transfer_buffer_memory/buffer_%d", transfer_buffer_->GetShmId()));
   dump->AddScalar(MemoryAllocatorDump::kNameSize,
@@ -455,11 +452,12 @@ bool GLES2Implementation::OnMemoryDump(
   if (args.level_of_detail != MemoryDumpLevelOfDetail::BACKGROUND) {
     dump->AddScalar("free_size", MemoryAllocatorDump::kUnitsBytes,
                     transfer_buffer_->GetFreeSize());
-    auto guid = GetBufferGUIDForTracing(tracing_process_id,
-                                        transfer_buffer_->GetShmId());
-    const int kImportance = 2;
-    pmd->CreateSharedGlobalAllocatorDump(guid);
-    pmd->AddOwnershipEdge(dump->guid(), guid, kImportance);
+    auto* shared_memory = transfer_buffer_->GetSharedMemory();
+    if (shared_memory) {
+      base::SharedMemoryTracker::AddOwnershipEdges(
+          pmd, dump->guid(), shared_memory->handle(),
+          shared_memory->mapped_size());
+    }
   }
 
   return true;