Fix MSVC build (including on 2015), drop some workarounds for MSVC older than 2013.

The Windows client gyp files were missing proc_maps_linux.cc for the
unittest build. Adding that revealed some build errors due to it
unconditionally including <inttypes.h>. Removing the workarounds in
breakpad_types.h (and a few other places) made that build, which means
that Visual C++ 2013 is now our minimum supported version of MSVC.

Additionally I tried building with VC++ 2015 and fixed a few warnings
(which were failing the build because we have /WX enabled) to ensure
that that builds as well.

BUG=https://code.google.com/p/google-breakpad/issues/detail?id=669
R=mark@chromium.org

Review URL: https://codereview.chromium.org/1353893002 .

src/google_breakpad/common/breakpad_types.h

@@ -40,35 +40,11 @@
 #ifndef GOOGLE_BREAKPAD_COMMON_BREAKPAD_TYPES_H__
 #define GOOGLE_BREAKPAD_COMMON_BREAKPAD_TYPES_H__
 
-#ifndef _WIN32
-
 #ifndef __STDC_FORMAT_MACROS
 #define __STDC_FORMAT_MACROS
 #endif  /* __STDC_FORMAT_MACROS */
 #include <inttypes.h>
 
-#else  /* !_WIN32 */
-
-#if _MSC_VER >= 1600
-#include <stdint.h>
-#elif defined(BREAKPAD_CUSTOM_STDINT_H)
-/* Visual C++ Pre-2010 did not ship a stdint.h, so allow
- * consumers of this library to provide their own because
- * there are often subtle type incompatibilities.
- */
-#include BREAKPAD_CUSTOM_STDINT_H
-#else
-#include <wtypes.h>
-
-typedef unsigned __int8  uint8_t;
-typedef unsigned __int16 uint16_t;
-typedef __int32 int32_t;
-typedef unsigned __int32 uint32_t;
-typedef unsigned __int64 uint64_t;
-#endif
-
-#endif  /* !_WIN32 */
-
 typedef struct {
   uint64_t high;
   uint64_t low;