Remove pointer mangling API from trace_event.h and use an addTraceEvent flag instead

base/debug/trace_event_impl.cc

 // Copyright (c) 2012 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 "base/debug/trace_event_impl.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
@@ skipping 577 matching lines @@
       // Determine whether to drop the begin/end pair.
       TimeDelta elapsed = now - logged_events_[begin_i].timestamp();
       if (elapsed < TimeDelta::FromMicroseconds(threshold)) {
         // Remove begin event and do not add end event.
         // This will be expensive if there have been other events in the
         // mean time (should be rare).
         logged_events_.erase(logged_events_.begin() + begin_i);
         return -1;
       }
     }
+
+    if (flags & TRACE_EVENT_FLAG_MANGLE_ID)
+      id ^= process_id_hash_;
+
     ret_begin_id = static_cast<int>(logged_events_.size());
     logged_events_.push_back(
         TraceEvent(thread_id,
                    now, phase, category_enabled, name, id,
                    num_args, arg_names, arg_types, arg_values,
                    flags));
 
     if (logged_events_.size() == kTraceEventBufferSize) {
       buffer_full_callback_copy = buffer_full_callback_;
     }
@@ skipping 102 matching lines @@
   // Create a FNV hash from the process ID for XORing.
   // See http://isthe.com/chongo/tech/comp/fnv/ for algorithm details.
   unsigned long long offset_basis = 14695981039346656037ull;
   unsigned long long fnv_prime = 1099511628211ull;
   unsigned long long pid = static_cast<unsigned long long>(process_id_);
   process_id_hash_ = (offset_basis ^ pid) * fnv_prime;
 }
 
 }  // namespace debug
 }  // namespace base