message: Clarify about static variables in logging.cc.
  Cr-Commit-Position: refs/heads/main@{#35554}
diff: @@ -55,13 +55,15 @@ namespace rtc {
  namespace {
  // By default, release builds don't log, debug builds at info level
  #if !defined(NDEBUG)
  -static LoggingSeverity g_min_sev = LS_INFO;
  -static LoggingSeverity g_dbg_sev = LS_INFO;
  +constexpr LoggingSeverity kDefaultLoggingSeverity = LS_INFO;
  #else
  -static LoggingSeverity g_min_sev = LS_NONE;
  -static LoggingSeverity g_dbg_sev = LS_NONE;
  +constexpr LoggingSeverity kDefaultLoggingSeverity = LS_NONE;
  #endif
  +// Note: `g_min_sev` and `g_dbg_sev` can be changed while running.
  +LoggingSeverity g_min_sev = kDefaultLoggingSeverity;
  +LoggingSeverity g_dbg_sev = kDefaultLoggingSeverity;
  +
  // Return the filename portion of the string (that following the last slash).
  const char* FilenameFromPath(const char* file) {
  const char* end1 = ::strrchr(file, '/');
  