fix typo: TOOD -> TODO (#448)

src/signalhandler.cc

@@ -169,7 +169,7 @@ void DumpTimeInfo() {
   g_failure_writer(buf, formatter.num_bytes_written());
 }
 
-// TOOD(hamaji): Use signal instead of sigaction?
+// TODO(hamaji): Use signal instead of sigaction?
 #ifdef HAVE_SIGACTION
 
 // Dumps information about the signal to STDERR.

src/utilities.cc

@@ -142,7 +142,7 @@ static void DumpStackTrace(int skip_count, DebugWriter *writerfn, void *arg) {
 static void DumpStackTraceAndExit() {
   DumpStackTrace(1, DebugWriteToStderr, NULL);
 
-  // TOOD(hamaji): Use signal instead of sigaction?
+  // TODO(hamaji): Use signal instead of sigaction?
   if (IsFailureSignalHandlerInstalled()) {
     // Set the default signal handler for SIGABRT, to avoid invoking our
     // own signal handler installed by InstallFailureSignalHandler().