Add function to compute proportional set size for OS_WIN

components/tracing/common/process_metrics_memory_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 "components/tracing/common/process_metrics_memory_dump_provider.h"
 
 #include <fcntl.h>
 #include <stdint.h>
 
 #include <map>
@@ skipping 280 matching lines @@
       is_rss_peak_resettable_ = false;
     }
     close(clear_refs_fd);
   }
 #elif defined(MACOSX)
   size_t private_bytes;
   bool res = process_metrics_->GetMemoryBytes(&private_bytes,
                                               nullptr /* shared_bytes */);
   if (res)
     pmd->process_totals()->SetExtraFieldInBytes("private_bytes", private_bytes);
-#endif  // defined(OS_LINUX) || defined(OS_ANDROID)
+#elif defined(OS_WIN)
+  if (args.level_of_detail ==
+      base::trace_event::MemoryDumpLevelOfDetail::DETAILED) {
+    uint64_t pss_bytes = 0;
+    bool res = process_metrics_->GetProportionalSetSizeBytes(&pss_bytes);
+    if (res) {
+      base::trace_event::ProcessMemoryMaps::VMRegion region;
+      region.byte_stats_proportional_resident = pss_bytes;
+      pmd->process_mmaps()->AddVMRegion(region);
+      pmd->set_has_process_mmaps();
+    }
+  }
+
+#endif
 #endif  // !defined(OS_IOS)
 
   pmd->process_totals()->set_resident_set_bytes(rss_bytes);
   pmd->set_has_process_totals();
   pmd->process_totals()->set_peak_resident_set_bytes(peak_rss_bytes);
 
   // Returns true even if other metrics failed, since rss is reported.
   return true;
 }
 
 }  // namespace tracing