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

cc/raster/staging_buffer_pool.cc

Index: cc/raster/staging_buffer_pool.cc
diff --git a/cc/raster/staging_buffer_pool.cc b/cc/raster/staging_buffer_pool.cc
index 6fa0fe03551d7604e93fdd6a5c89a2f502704a5e..252a727463111146ead385709dba774397360dc3 100644
--- a/cc/raster/staging_buffer_pool.cc
+++ b/cc/raster/staging_buffer_pool.cc
@@ -8,6 +8,7 @@
 
 #include "base/memory/memory_coordinator_client_registry.h"
 #include "base/memory/ptr_util.h"
+#include "base/memory/shared_memory_tracker.h"
 #include "base/strings/stringprintf.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/trace_event/memory_dump_manager.h"
@@ -111,17 +112,14 @@ void StagingBuffer::OnMemoryDump(base::trace_event::ProcessMemoryDump* pmd,
                          in_free_list ? buffer_size_in_bytes : 0);
 
   // Emit an ownership edge towards a global allocator dump node.
-  const uint64_t tracing_process_id =
-      base::trace_event::MemoryDumpManager::GetInstance()
-          ->GetTracingProcessId();
-  MemoryAllocatorDumpGuid shared_buffer_guid =
-      gfx::GetGpuMemoryBufferGUIDForTracing(tracing_process_id, buffer_id);
-  pmd->CreateSharedGlobalAllocatorDump(shared_buffer_guid);
 
   // By creating an edge with a higher |importance| (w.r.t. browser-side dumps)
   // the tracing UI will account the effective size of the buffer to the child.
-  const int kImportance = 2;
-  pmd->AddOwnershipEdge(buffer_dump->guid(), shared_buffer_guid, kImportance);
+  // const int kImportance = 2;
+  // TODO(hajimehoshi): Importance
+  base::SharedMemoryTracker::AddOwnershipEdges(
+      pmd, buffer_dump->guid(), gpu_memory_buffer->GetHandle().handle,
+      buffer_size_in_bytes);
 }
 
 StagingBufferPool::StagingBufferPool(base::SequencedTaskRunner* task_runner,