base: Support setting thread priorities generically.

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/leak_annotations.h"
@@ skipping 959 matching lines @@
         << "Cannot manipulate TraceLog::Enabled state from an observer.";
     return;
   }
 
   if (sampling_thread_.get()) {
     // Stop the sampling thread.
     sampling_thread_->Stop();
     lock_.Release();
     PlatformThread::Join(sampling_thread_handle_);
     lock_.Acquire();
-    sampling_thread_handle_ = 0;
+    sampling_thread_handle_ = PlatformThreadHandle();
     sampling_thread_.reset();
   }
 
   dispatching_to_observer_list_ = true;
   FOR_EACH_OBSERVER(EnabledStateChangedObserver,
                     enabled_state_observer_list_,
                     OnTraceLogWillDisable());
   dispatching_to_observer_list_ = false;
 
   category_filter_.Clear();
@@ skipping 511 matching lines @@
         NULL,                    // arg_names
         NULL,                    // arg_types
         NULL,                    // arg_values
         NULL,                    // convertable values
         TRACE_EVENT_FLAG_NONE);  // flags
   }
 }
 
 }  // namespace trace_event_internal