Add test for RAF-spinning with no damage

base/test/trace_event_analyzer.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.
 
 // Use trace_analyzer::Query and trace_analyzer::TraceAnalyzer to search for
 // specific trace events that were generated by the trace_event.h API.
 //
 // Basic procedure:
 // - Get trace events JSON string from base::debug::TraceLog.
 // - Create TraceAnalyzer with JSON string.
@@ skipping 535 matching lines @@
 
 // Utility functions for TraceEventVector.
 
 struct RateStats {
   double min_us;
   double max_us;
   double mean_us;
   double standard_deviation_us;
 };
 
+struct RateStatsOptions {
+  RateStatsOptions() : trim_min(0u), trim_max(0u) {}
+  // After the times between events are sorted, the number of specified elements
+  // will be trimmed before calculating the RateStats. This is useful in cases
+  // where extreme outliers are tolerable and should not skew the overall
+  // average.
+  size_t trim_min;  // Trim this many minimum times.
+  size_t trim_max;  // Trim this many maximum times.
+};
+
 // Calculate min/max/mean and standard deviation from the times between
 // adjacent events.
-bool GetRateStats(const TraceEventVector& events, RateStats* stats);
+bool GetRateStats(const TraceEventVector& events,
+                  RateStats* stats,
+                  const RateStatsOptions* options);
 
 // Starting from |position|, find the first event that matches |query|.
 // Returns true if found, false otherwise.
 bool FindFirstOf(const TraceEventVector& events,
                  const Query& query,
                  size_t position,
                  size_t* return_index);
 
 // Starting from |position|, find the last event that matches |query|.
 // Returns true if found, false otherwise.
@@ skipping 21 matching lines @@
 
 // Count all matches.
 static inline size_t CountMatches(const TraceEventVector& events,
                                   const Query& query) {
   return CountMatches(events, query, 0u, events.size());
 }
 
 }  // namespace trace_analyzer
 
 #endif  // BASE_TEST_TRACE_EVENT_ANALYZER_H_