guid_creater: include string.h for memcpy

Bug: google-breakpad:779
Change-Id: If0cfb036ee924178033c89d4dc3e2ce75ddd46f2
Reviewed-on: https://chromium-review.googlesource.com/c/breakpad/breakpad/+/1732887
Reviewed-by: Mark Mentovai <mark@chromium.org>
diff --git a/src/common/linux/guid_creator.cc b/src/common/linux/guid_creator.cc
index f81c291..03e3d78 100644
--- a/src/common/linux/guid_creator.cc
+++ b/src/common/linux/guid_creator.cc
@@ -39,6 +39,7 @@
 #include <pthread.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <sys/stat.h>
 #include <time.h>
 #include <unistd.h>