122   struct CollectionContext {  struct in base::StackSamplingProfiler::SamplingThread
123     CollectionContext(PlatformThreadId thread_id,  in CollectionContext()  argument
138     const int collection_id;
139     const PlatformThreadId thread_id;  // Thread id of the sampled thread.
141     const SamplingParams params;    // Information about how to sample.
143         finished;  // Signaled when all sampling complete.
146     std::unique_ptr<ProfileBuilder> profile_builder;
149     std::unique_ptr<StackSampler> sampler;
152     TimeTicks next_sample_time;
155     TimeTicks profile_start_time;
158     int sample_count = 0;
161     static AtomicSequenceNumber next_collection_id;