Add new wired memory metric to memory-infra dumps.

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 594 matching lines @@
   return res;
 }
 
 bool ProcessMetricsMemoryDumpProvider::DumpProcessTotals(
     const base::trace_event::MemoryDumpArgs& args,
     base::trace_event::ProcessMemoryDump* pmd) {
 #if defined(OS_MACOSX)
   size_t private_bytes;
   size_t shared_bytes;
   size_t resident_bytes;
+  size_t wired_bytes;
   if (!process_metrics_->GetMemoryBytes(&private_bytes, &shared_bytes,
-                                        &resident_bytes)) {
+                                        &resident_bytes, &wired_bytes)) {
     return false;
   }
   uint64_t rss_bytes = resident_bytes;
   pmd->process_totals()->SetExtraFieldInBytes("private_bytes", private_bytes);
   pmd->process_totals()->SetExtraFieldInBytes("shared_bytes", shared_bytes);
+  pmd->process_totals()->SetExtraFieldInBytes("user_wired_bytes", wired_bytes);

[Primiano Tucci (use gerrit), 2017/03/28 20:32:54]

is the "user_" part important? just worrying about column width on the UI.
Also, not sure about what the real semantic of "wired" is, but maybe
"locked_bytes" might be more user friendly? really up to you, I'm fine in any
case

[erikchen, 2017/03/30 00:03:14]

Done.

 #else
   uint64_t rss_bytes = process_metrics_->GetWorkingSetSize();
 #endif  // defined(OS_MACOSX)
   if (rss_bytes_for_testing)
     rss_bytes = rss_bytes_for_testing;
 
   // rss_bytes will be 0 if the process ended while dumping.
   if (!rss_bytes)
     return false;
 
@@ skipping 72 matching lines @@
 #endif
 }
 
 void ProcessMetricsMemoryDumpProvider::SuspendFastMemoryPolling() {
 #if defined(OS_LINUX) || defined(OS_ANDROID)
   fast_polling_statm_fd_.reset();
 #endif
 }
 
 }  // namespace tracing