third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/src/google/protobuf/stubs/platform_macros.h

Index: third_party/protobuf/src/google/protobuf/stubs/platform_macros.h
diff --git a/third_party/protobuf/src/google/protobuf/stubs/platform_macros.h b/third_party/protobuf/src/google/protobuf/stubs/platform_macros.h
index 4ba4b348c74fcc37cdd5b67e963c654909788ea7..7a54060dfa31ace3bf4ea94710bc727f6d6a03b8 100644
--- a/third_party/protobuf/src/google/protobuf/stubs/platform_macros.h
+++ b/third_party/protobuf/src/google/protobuf/stubs/platform_macros.h
@@ -47,7 +47,7 @@
 #elif defined(__QNX__)
 #define GOOGLE_PROTOBUF_ARCH_ARM_QNX 1
 #define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(__ARMEL__)
+#elif defined(_M_ARM) || defined(__ARMEL__)
 #define GOOGLE_PROTOBUF_ARCH_ARM 1
 #define GOOGLE_PROTOBUF_ARCH_32_BIT 1
 #elif defined(__aarch64__)
@@ -114,11 +114,11 @@ GOOGLE_PROTOBUF_PLATFORM_ERROR
 
 #undef GOOGLE_PROTOBUF_PLATFORM_ERROR
 
-#if defined(GOOGLE_PROTOBUF_OS_ANDROID) || defined(GOOGLE_PROTOBUF_OS_IPHONE)
+#if defined(GOOGLE_PROTOBUF_OS_ANDROID) || defined(GOOGLE_PROTOBUF_OS_IPHONE) || defined(__OpenBSD__)
 // Android ndk does not support the __thread keyword very well yet. Here
 // we use pthread_key_create()/pthread_getspecific()/... methods for
 // TLS support on android.
-// iOS also does not support the __thread keyword.
+// iOS and OpenBSD also do not support the __thread keyword.
 #define GOOGLE_PROTOBUF_NO_THREADLOCAL
 #endif