msvcp: Implement the WCHAR version of _Symlink.

dlls/msvcp120/msvcp120.spec

@@ -1734,8 +1734,8 @@
 @ cdecl -arch=win64 ?_Swap_all@_Container_base12@std@@QEAAXAEAU12@@Z(ptr ptr) _Container_base12__Swap_all
 @ cdecl -arch=win32 ?_Symlink@sys@tr2@std@@YAHPBD0@Z(str str) tr2_sys__Symlink
 @ cdecl -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEBD0@Z(str str) tr2_sys__Symlink
-@ stub -arch=win32 ?_Symlink@sys@tr2@std@@YAHPB_W0@Z
-@ stub -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEB_W0@Z
+@ cdecl -arch=win32 ?_Symlink@sys@tr2@std@@YAHPB_W0@Z(wstr wstr) tr2_sys__Symlink_wchar
+@ cdecl -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEB_W0@Z(wstr wstr) tr2_sys__Symlink_wchar
 @ extern ?_Sync@ios_base@std@@0_NA ios_base_Sync
 @ stub -arch=win32 ?_Syserror_map@std@@YAPBDH@Z
 @ stub -arch=win64 ?_Syserror_map@std@@YAPEBDH@Z

dlls/msvcp120_app/msvcp120_app.spec

@@ -1734,8 +1734,8 @@
 @ cdecl -arch=win64 ?_Swap_all@_Container_base12@std@@QEAAXAEAU12@@Z(ptr ptr) msvcp120.?_Swap_all@_Container_base12@std@@QEAAXAEAU12@@Z
 @ cdecl -arch=win32 ?_Symlink@sys@tr2@std@@YAHPBD0@Z(str str) msvcp120.?_Symlink@sys@tr2@std@@YAHPBD0@Z
 @ cdecl -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEBD0@Z(str str) msvcp120.?_Symlink@sys@tr2@std@@YAHPEBD0@Z
-@ stub -arch=win32 ?_Symlink@sys@tr2@std@@YAHPB_W0@Z
-@ stub -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEB_W0@Z
+@ cdecl -arch=win32 ?_Symlink@sys@tr2@std@@YAHPB_W0@Z(wstr wstr) msvcp120.?_Symlink@sys@tr2@std@@YAHPB_W0@Z
+@ cdecl -arch=win64 ?_Symlink@sys@tr2@std@@YAHPEB_W0@Z(wstr wstr) msvcp120.?_Symlink@sys@tr2@std@@YAHPEB_W0@Z
 @ extern ?_Sync@ios_base@std@@0_NA msvcp120.?_Sync@ios_base@std@@0_NA
 @ stub -arch=win32 ?_Syserror_map@std@@YAPBDH@Z
 @ stub -arch=win64 ?_Syserror_map@std@@YAPEBDH@Z

dlls/msvcp140/msvcp140.spec

@@ -3716,7 +3716,7 @@
 @ cdecl _Stoulx(ptr ptr long ptr) _Stoulx
 @ cdecl _Strcoll(ptr ptr ptr ptr ptr) _Strcoll
 @ stub _Strxfrm
-@ stub _Symlink
+@ cdecl _Symlink(wstr wstr) tr2_sys__Symlink_wchar
 @ stub _Symlink_get
 @ stub _Temp_get
 @ stub _Thrd_abort

dlls/msvcp90/ios.c

@@ -15049,6 +15049,20 @@ int __cdecl tr2_sys__Symlink(char const* existing_file_name, char const* file_na
     return GetLastError();
 }
 
+/* ?_Symlink@sys@tr2@std@@YAHPB_W0@Z */
+/* ?_Symlink@sys@tr2@std@@YAHPEB_W0@Z */
+/* _Symlink */
+int __cdecl tr2_sys__Symlink_wchar(WCHAR const* existing_file_name, WCHAR const* file_name)
+{
+    TRACE("(%s %s)\n", debugstr_w(existing_file_name), debugstr_w(file_name));
+    if(!existing_file_name || !file_name)
+        return ERROR_INVALID_PARAMETER;
+
+    if(CreateSymbolicLinkW(file_name, existing_file_name, 0))
+        return ERROR_SUCCESS;
+    return GetLastError();
+}
+
 /* ?_Unlink@sys@tr2@std@@YAHPBD@Z */
 /* ?_Unlink@sys@tr2@std@@YAHPEBD@Z */
 int __cdecl tr2_sys__Unlink(char const* path)