win: Move NTDDI_VERSION into winver, stop setting it for usrsctp

third_party/usrsctp/usrsctp.gyp

Index: third_party/usrsctp/usrsctp.gyp
diff --git a/third_party/usrsctp/usrsctp.gyp b/third_party/usrsctp/usrsctp.gyp
index 9533fb8ed12e0b0c8e7c71a76280a421cbbdd032..cfae0487df0d9a2a23839e01ac9979effb0191f9 100644
--- a/third_party/usrsctp/usrsctp.gyp
+++ b/third_party/usrsctp/usrsctp.gyp
@@ -106,7 +106,7 @@
         ['OS=="linux" or OS=="android"', {
           'defines': [
             '__Userspace_os_Linux',
-	    '_GNU_SOURCE'
+            '_GNU_SOURCE'
           ],
           'cflags!': [ '-Werror', '-Wall' ],
           'cflags': [ '-w' ],
@@ -130,16 +130,6 @@
         ['OS=="win"', {
           'defines': [
             '__Userspace_os_Windows',
-            # Manually setting WINVER and _WIN32_WINNT is needed because Chrome
-            # sets WINVER to a newer version of Windows. But compiling usrsctp
-            # this way would be incompatible with Windows XP.
-            'WINVER=0x0502',
-            '_WIN32_WINNT=0x0502',
-          ],
-          'defines!': [
-            # Remove Chrome's WINVER defines to avoid redefinition warnings.
-            'WINVER=0x0A00',
-            '_WIN32_WINNT=0x0A00',
           ],
           'cflags!': [ '/W3', '/WX' ],
           'cflags': [ '/w' ],