[Tracing] Remove context_id in favor of traits

base/trace_event/trace_event_impl.h

 // 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.
 
 
 #ifndef BASE_TRACE_EVENT_TRACE_EVENT_IMPL_H_
 #define BASE_TRACE_EVENT_TRACE_EVENT_IMPL_H_
 
 #include <stack>
 #include <string>
@@ skipping 83 matching lines @@
   void CopyFrom(const TraceEvent& other);
 
   void Initialize(
       int thread_id,
       TimeTicks timestamp,
       ThreadTicks thread_timestamp,
       char phase,
       const unsigned char* category_group_enabled,
       const char* name,
       unsigned long long id,
-      unsigned long long context_id,
       unsigned long long bind_id,
       int num_args,
       const char** arg_names,
       const unsigned char* arg_types,
       const unsigned long long* arg_values,
       const scoped_refptr<ConvertableToTraceFormat>* convertable_values,
       unsigned int flags);
 
   void Reset();
 
@@ skipping 11 matching lines @@
                                 TraceValue value,
                                 std::string* out);
 
   TimeTicks timestamp() const { return timestamp_; }
   ThreadTicks thread_timestamp() const { return thread_timestamp_; }
   char phase() const { return phase_; }
   int thread_id() const { return thread_id_; }
   TimeDelta duration() const { return duration_; }
   TimeDelta thread_duration() const { return thread_duration_; }
   unsigned long long id() const { return id_; }
-  unsigned long long context_id() const { return context_id_; }
   unsigned int flags() const { return flags_; }
 
   // Exposed for unittesting:
 
   const base::RefCountedString* parameter_copy_storage() const {
     return parameter_copy_storage_.get();
   }
 
   const unsigned char* category_group_enabled() const {
     return category_group_enabled_;
   }
 
   const char* name() const { return name_; }
 
 #if defined(OS_ANDROID)
   void SendToATrace();
 #endif
 
  private:
   // Note: these are ordered by size (largest first) for optimal packing.
   TimeTicks timestamp_;
   ThreadTicks thread_timestamp_;
   TimeDelta duration_;
   TimeDelta thread_duration_;
   // id_ can be used to store phase-specific data.
   unsigned long long id_;
-  // context_id_ is used to store context information.
-  unsigned long long context_id_;
   TraceValue arg_values_[kTraceMaxNumArgs];
   const char* arg_names_[kTraceMaxNumArgs];
   scoped_refptr<ConvertableToTraceFormat> convertable_values_[kTraceMaxNumArgs];
   const unsigned char* category_group_enabled_;
   const char* name_;
   scoped_refptr<base::RefCountedString> parameter_copy_storage_;
   // Depending on TRACE_EVENT_FLAG_HAS_PROCESS_ID the event will have either:
   //  tid: thread_id_, pid: current_process_id (default case).
   //  tid: -1, pid: process_id_ (when flags_ & TRACE_EVENT_FLAG_HAS_PROCESS_ID).
   union {
     int thread_id_;
     int process_id_;
   };
   unsigned int flags_;
   unsigned long long bind_id_;
   unsigned char arg_types_[kTraceMaxNumArgs];
   char phase_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceEvent);
 };
 
 }  // namespace trace_event
 }  // namespace base
 
 #endif  // BASE_TRACE_EVENT_TRACE_EVENT_IMPL_H_