Set allow_user_segv_handler asan option

sanitizers/sanitizer_options.cc

Index: sanitizers/sanitizer_options.cc
diff --git a/sanitizers/sanitizer_options.cc b/sanitizers/sanitizer_options.cc
index 81958f214deab4d5163ffcd0cc29db0572f5cac1..1888d4b5e90acbf397d4c4d58757812aaf2cb6ce 100644
--- a/sanitizers/sanitizer_options.cc
+++ b/sanitizers/sanitizer_options.cc
@@ -66,13 +66,15 @@ void _sanitizer_options_link_helper() { }
 const char kAsanDefaultOptions[] =
     "legacy_pthread_cond=1 malloc_context_size=5 "
     "symbolize=1 check_printf=1 use_sigaltstack=1 detect_leaks=0 "
-    "strip_path_prefix=/../../ fast_unwind_on_fatal=1";
+    "strip_path_prefix=/../../ fast_unwind_on_fatal=1"
+    "allow_user_segv_handler=1 ";
 #else
 // Default AddressSanitizer options for buildbots and non-official builds.
 const char *kAsanDefaultOptions =
     "symbolize=1 check_printf=1 use_sigaltstack=1 "
     "detect_leaks=0 strip_path_prefix=/../../ fast_unwind_on_fatal=1 "
-    "detect_stack_use_after_return=1 ";
+    "detect_stack_use_after_return=1 "
+    "allow_user_segv_handler=1 ";
 #endif  // GOOGLE_CHROME_BUILD
 
 #elif defined(OS_MACOSX)