Bug 724283 - Building with NSIS 2.33u restricts installation on all service packs of Windows XP. r=rstrong

toolkit/mozapps/installer/windows/nsis/overrides.nsh

@@ -134,8 +134,11 @@
     !insertmacro __WinVer_Call_GetVersionEx ${OSVERSIONINFOW_SIZE}
   _winver_ex:
 
-  # get results from struct
-  System::Call '*$0(i.s,i.r1,i.r2,i.r3,i.s,&t128.s,&i2.s,&i2,&i2,&i1.s,&i1)'
+  # The original struct formatting string here was:
+  # '*$0(i.s,i.r1,i.r2,i.r3,i.s,&t128.s,&i2.s,&i2,&i2,&i1.s,&i1)'
+  # but in NSIS v2.33u strings take the size in bytes instead of size in chars
+  # so the 128 char '&t128.s' is changed here to '&t256.s'. 
+  System::Call '*$0(i.s,i.r1,i.r2,i.r3,i.s,&t256.s,&i2.s,&i2,&i2,&i1.s,&i1)'
 
   # free struct
   System::Free $0