user32: Return Unicode length instead of ANSI in GetUserObjectInformationA.

dlls/user32/tests/winstation.c

@@ -397,7 +397,7 @@ static void test_getuserobjectinformation(void)
 
     ok(!ret, "GetUserObjectInformationA returned %x", ret);
     ok(GetLastError() == ERROR_INSUFFICIENT_BUFFER, "LastError is set to %08x\n", GetLastError());
-    todo_wine ok(size == 22, "size is set to %d\n", size); /* Windows returns Unicode length (11*2) */
+    ok(size == 22, "size is set to %d\n", size); /* Windows returns Unicode length (11*2) */
 
     /* Get string */
     SetLastError(0xdeadbeef);
@@ -439,7 +439,7 @@ static void test_getuserobjectinformation(void)
 
     ok(!ret, "GetUserObjectInformationA returned %x", ret);
     ok(GetLastError() == ERROR_INSUFFICIENT_BUFFER, "LastError is set to %08x\n", GetLastError());
-    todo_wine ok(size == 16, "size is set to %d\n", size); /* Windows returns Unicode length (8*2) */
+    ok(size == 16, "size is set to %d\n", size); /* Windows returns Unicode length (8*2) */
 
     /* Get string */
     SetLastError(0xdeadbeef);

dlls/user32/winstation.c

@@ -477,13 +477,17 @@ BOOL WINAPI GetUserObjectInformationA( HANDLE handle, INT index, LPVOID info, DW
     if (index == UOI_TYPE || index == UOI_NAME)
     {
         WCHAR buffer[MAX_PATH];
-        DWORD lenA;
+        DWORD lenA, lenW;
 
-        if (!GetUserObjectInformationW( handle, index, buffer, sizeof(buffer), NULL )) return FALSE;
+        if (!GetUserObjectInformationW( handle, index, buffer, sizeof(buffer), &lenW )) return FALSE;
         lenA = WideCharToMultiByte( CP_ACP, 0, buffer, -1, NULL, 0, NULL, NULL );
         if (needed) *needed = lenA;
         if (lenA > len)
         {
+            /* If the buffer length supplied by the caller is insufficient, Windows returns a
+               'needed' length based upon the Unicode byte length, so we should do similarly. */
+            if (needed) *needed = lenW;
+
             SetLastError( ERROR_INSUFFICIENT_BUFFER );
             return FALSE;
         }