reworked comment for complexity report

include/benchmark/reporter.h

@@ -93,8 +93,8 @@ class BenchmarkReporter {
   // benchmark, thus have the same name.
   virtual void ReportRuns(const std::vector<Run>& report) = 0;
   
-  // Called once at the last instance of a benchmark range, gives information about
-  // asymptotic complexity and RMS. 
+  // Called once at the last benchmark in a family of benchmarks, gives information
+  // about asymptotic complexity and RMS. 
   // Note that all the benchmark runs in a range should refer to the same benchmark, 
   // thus have the same name.
   virtual void ReportComplexity(const std::vector<Run>& complexity_reports) = 0;