[presubmit] Enable runtime/threadsafe_fn linter checking.

src/base/platform/platform-solaris.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Platform-specific code for Solaris 10 goes here. For the POSIX-compatible
 // parts, the implementation is in platform-posix.cc.
 
 #ifdef __sparc
 # error "V8 does not support the SPARC CPU architecture."
 #endif
@@ skipping 20 matching lines @@
 #include "src/base/platform/platform.h"
 
 
 namespace v8 {
 namespace base {
 
 
 const char* OS::LocalTimezone(double time, TimezoneCache* cache) {
   if (std::isnan(time)) return "";
   time_t tv = static_cast<time_t>(std::floor(time/msPerSecond));
-  struct tm* t = localtime(&tv);
+  struct tm* t = localtime(&tv);  // NOLINT(runtime/threadsafe_fn)
   if (NULL == t) return "";
   return tzname[0];  // The location of the timezone string on Solaris.
 }
 
 
 double OS::LocalTimeOffset(TimezoneCache* cache) {
   tzset();
   return -static_cast<double>(timezone * msPerSecond);
 }
 
@@ skipping 150 matching lines @@
   return munmap(base, size) == 0;
 }
 
 
 bool VirtualMemory::HasLazyCommits() {
   // TODO(alph): implement for the platform.
   return false;
 }
 
 } }  // namespace v8::base