Added a whitelist for trace events that are known to be PII-less.

content/browser/tracing/tracing_controller_impl.cc

 // Copyright (c) 2013 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 "content/browser/tracing/tracing_controller_impl.h"
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/json/string_escape.h"
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/trace_event/trace_event.h"
 #include "content/browser/tracing/trace_message_filter.h"
 #include "content/browser/tracing/tracing_ui.h"
 #include "content/common/child_process_messages.h"
 #include "content/public/browser/browser_message_filter.h"
+#include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/debug_daemon_client.h"
 #endif
 
 #if defined(OS_WIN)
 #include "content/browser/tracing/etw_system_event_consumer_win.h"
 #endif
@@ skipping 63 matching lines @@
 
 void TracingControllerImpl::SetEnabledOnFileThread(
     const CategoryFilter& category_filter,
     int mode,
     const TraceOptions& trace_options,
     const base::Closure& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
 
   TraceLog::GetInstance()->SetEnabled(
       category_filter, static_cast<TraceLog::Mode>(mode), trace_options);
+  if (trace_options.enable_args_whitelist) {
+    TraceLog::GetInstance()->SetEventFilterPredicate(
+        GetContentClient()->GetTraceEventFilterPredicate());

[jam, 2015/05/12 23:16:32]

why do you need to change content?  seems like chrome can call TraceLog
directly?

[oystein (OOO til 10th of July), 2015/05/12 23:25:12]

Tracing is primarily a content/ concept; there's no initialization of tracing
done in chrome/, so I'd have to add some new hook points there. The predicate
also needs to be accessible from content/public/ for the sake of
components/tracing/ anyway, so I'm not sure if setting this from chrome/ gains
us anything?

+  }
+
   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, callback);
 }
 
 void TracingControllerImpl::SetDisabledOnFileThread(
     const base::Closure& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::FILE);
 
   TraceLog::GetInstance()->SetDisabled();
   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE, callback);
 }
@@ skipping 761 matching lines @@
   is_monitoring_ = is_monitoring;
 #if !defined(OS_ANDROID)
   for (std::set<TracingUI*>::iterator it = tracing_uis_.begin();
        it != tracing_uis_.end(); it++) {
     (*it)->OnMonitoringStateChanged(is_monitoring);
   }
 #endif
 }
 
 }  // namespace content