Update from https://crrev.com/306655

net/tools/dump_cache/simple_cache_dumper.cc

Index: net/tools/dump_cache/simple_cache_dumper.cc
diff --git a/net/tools/dump_cache/simple_cache_dumper.cc b/net/tools/dump_cache/simple_cache_dumper.cc
index dd5ecbf15f65c010896502d80379468257fa7f06..9be140dd4518d2cef729c55bc8921c22c6b7d111 100644
--- a/net/tools/dump_cache/simple_cache_dumper.cc
+++ b/net/tools/dump_cache/simple_cache_dumper.cc
@@ -10,6 +10,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/message_loop/message_loop_proxy.h"
+#include "base/profiler/scoped_tracker.h"
 #include "base/threading/thread.h"
 #include "net/base/cache_type.h"
 #include "net/base/io_buffer.h"
@@ -260,6 +261,11 @@ int SimpleCacheDumper::DoWriteBodyComplete(int rv) {
 }
 
 void SimpleCacheDumper::OnIOComplete(int rv) {
+  // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
+  tracked_objects::ScopedTracker tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "422516 SimpleCacheDumper::OnIOComplete"));
+
   rv = DoLoop(rv);
 
   if (rv != ERR_IO_PENDING) {