message: require semicolon after DEFINE_* and DECLARE_*
  Summary: fb303's DECLARE_ and DEFINE_ macros are a common source of extra semicolons. To satisfy both -Wextra-semi and clang-format, require semicolons after the macro instantiation.
diff: @@ -1103,23 +1103,22 @@ inline fb303::ThreadCachedServiceData& tcData() {
  } // namespace facebook
  #define DECLARE_timeseries(varname) \
  - extern ::facebook::fb303::TimeseriesWrapper STATS_##varname;
  + extern ::facebook::fb303::TimeseriesWrapper STATS_##varname
  #define DECLARE_histogram(varname) \
  - extern ::facebook::fb303::HistogramWrapper STATS_##varname;
  + extern ::facebook::fb303::HistogramWrapper STATS_##varname
  #define DECLARE_dynamic_timeseries(varname, keyNumArgs) \
  - extern ::facebook::fb303::DynamicTimeseriesWrapper<keyNumArgs> \
  - STATS_##varname;
  + extern ::facebook::fb303::DynamicTimeseriesWrapper<keyNumArgs> STATS_##varname
  #define DECLARE_dynamic_histogram(varname, keyNumArgs) \
  - extern ::facebook::fb303::DynamicHistogramWrapper<keyNumArgs> STATS_##varname;
  + extern ::facebook::fb303::DynamicHistogramWrapper<keyNumArgs> STATS_##varname
  #define DEFINE_timeseries(varname, ...) \
  - ::facebook::fb303::TimeseriesWrapper STATS_##varname(#varname, ##__VA_ARGS__);
  + ::facebook::fb303::TimeseriesWrapper STATS_##varname(#varname, ##__VA_ARGS__)
  #define DEFINE_histogram(varname, ...) \
  - ::facebook::fb303::HistogramWrapper STATS_##varname(#varname, ##__VA_ARGS__);
  + ::facebook::fb303::HistogramWrapper STATS_##varname(#varname, ##__VA_ARGS__)
  // We use this function to extract the number of placeholders from our keyformat
  // at compile-time.
  @@ -1140,7 +1139,7 @@ constexpr int countPlaceholders(folly::StringPiece keyformat) {
  countPlaceholders(keyformat) > 0, \
  "Must have at least one placeholder."); \
  ::facebook::fb303::DynamicTimeseriesWrapper<countPlaceholders(keyformat)> \
  - STATS_##varname(keyformat, {__VA_ARGS__});
  + STATS_##varname(keyformat, {__VA_ARGS__})
  #define DEFINE_dynamic_histogram( \
  varname, keyformat, bucketWidth, min, max, ...) \
  @@ -1148,4 +1147,4 @@ constexpr int countPlaceholders(folly::StringPiece keyformat) {
  countPlaceholders(keyformat) > 0, \
  "Must have at least one placeholder."); \
  ::facebook::fb303::DynamicHistogramWrapper<countPlaceholders(keyformat)> \
  - STATS_##varname(keyformat, bucketWidth, min, max, __VA_ARGS__);
  + STATS_##varname(keyformat, bucketWidth, min, max, __VA_ARGS__)
  