Revert linuxthreads.cc in r175186

third_party/tcmalloc/chromium/src/base/linuxthreads.cc

Index: third_party/tcmalloc/chromium/src/base/linuxthreads.cc
diff --git a/third_party/tcmalloc/chromium/src/base/linuxthreads.cc b/third_party/tcmalloc/chromium/src/base/linuxthreads.cc
index 47ffe817dc393e69947de8987dd9daae782b0de7..19da4004b17eaec47697afc4369e5a648969c88d 100644
--- a/third_party/tcmalloc/chromium/src/base/linuxthreads.cc
+++ b/third_party/tcmalloc/chromium/src/base/linuxthreads.cc
@@ -193,7 +193,7 @@ static volatile int *sig_pids, sig_num_threads, sig_proc, sig_marker;
 /* Signal handler to help us recover from dying while we are attached to
  * other threads.
  */
-static void SignalHandler(int signum, struct siginfo *si, void *data) {
+static void SignalHandler(int signum, siginfo_t *si, void *data) {
   if (sig_pids != NULL) {
     if (signum == SIGABRT) {
       while (sig_num_threads-- > 0) {