third_party/protobuf: Update to HEAD (f52e188fe4)

third_party/protobuf/patches/0004-fix-integer-types-and-shared-library-exports.patch

 --- protobuf-cleaned/src/google/protobuf/stubs/port.h   2015-12-30 13:21:46.000000000 -0800
 +++ protobuf-patched/src/google/protobuf/stubs/port.h   2016-03-31 13:25:26.840024811 -0700
 @@ -66,18 +66,34 @@
      #define PROTOBUF_LITTLE_ENDIAN 1
    #endif
  #endif
 -#if defined(_MSC_VER) && defined(PROTOBUF_USE_DLLS)
 -  #ifdef LIBPROTOBUF_EXPORTS
 -    #define LIBPROTOBUF_EXPORT __declspec(dllexport)
 -  #else
@@ skipping 28 matching lines @@
 +      #define LIBPROTOC_EXPORT   __attribute__((visibility("default")))
 +    #else
 +      #define LIBPROTOC_EXPORT
 +    #endif
    #endif
 -#else
 +#else  // defined(COMPONENT_BUILD) && defined(PROTOBUF_USE_DLLS)
    #define LIBPROTOBUF_EXPORT
    #define LIBPROTOC_EXPORT
  #endif
-@@ -109,15 +125,15 @@
- typedef unsigned __int32 uint32;
- typedef unsigned __int64 uint64;
- #else
--typedef signed char  int8;
--typedef short int16;
--typedef int int32;
--typedef long long int64;
--
--typedef unsigned char  uint8;
--typedef unsigned short uint16;
--typedef unsigned int uint32;
--typedef unsigned long long uint64;
-+typedef int8_t  int8;
-+typedef int16_t int16;
-+typedef int32_t int32;
-+typedef int64_t int64;
-+
-+typedef uint8_t  uint8;
-+typedef uint16_t uint16;
-+typedef uint32_t uint32;
-+typedef uint64_t uint64;
- #endif
- 
- // long long macros to be used because gcc and vc++ use different suffixes,
-@@ -131,8 +147,8 @@
- #define GOOGLE_ULONGLONG(x) x##UI64
+@@ -149,9 +149,9 @@
  #define GOOGLE_LL_FORMAT "I64"  // As in printf("%I64d", ...)
  #else
+ // By long long, we actually mean int64.
 -#define GOOGLE_LONGLONG(x) x##LL
 -#define GOOGLE_ULONGLONG(x) x##ULL
 +#define GOOGLE_LONGLONG(x) INT64_C(x)
 +#define GOOGLE_ULONGLONG(x) UINT64_C(x)
+ // Used to format real long long integers.
  #define GOOGLE_LL_FORMAT "ll"  // As in "%lld". Note that "q" is poor form also.
  #endif