comdlg32/tests: Don't test function directly when reporting GetLastError().

dlls/comdlg32/tests/filedlg.c

@@ -647,8 +647,10 @@ static void test_ok(void)
     char curdir[MAX_PATH];
     int i;
     DWORD ret;
+    BOOL cdret;
 
-    ok(GetCurrentDirectoryA(sizeof(curdir), curdir) != 0, "Failed to get current dir err %d\n", GetLastError());
+    cdret = GetCurrentDirectoryA(sizeof(curdir), curdir);
+    ok(cdret, "Failed to get current dir err %d\n", GetLastError());
     if (!GetTempFileNameA(".", "txt", 0, tmpfilename)) {
         skip("Failed to create a temporary file name\n");
         return;
@@ -671,7 +673,8 @@ static void test_ok(void)
         ok(ret == ok_testcases[i].expclose, "testid %d: GetOpenFileName returned %#x\n", i, ret);
         ret = CommDlgExtendedError();
         ok(!ret, "CommDlgExtendedError returned %#x\n", ret);
-        ok(SetCurrentDirectoryA(curdir), "Failed to restore current dir err %d\n", GetLastError());
+        cdret = SetCurrentDirectoryA(curdir);
+        ok(cdret, "Failed to restore current dir err %d\n", GetLastError());
     }
     ret =  DeleteFileA( tmpfilename);
     ok( ret, "Failed to delete temporary file %s err %d\n", tmpfilename, GetLastError());
@@ -1057,8 +1060,10 @@ static void test_extension(void)
     char *filename_ptr;
     const char *test_file_name = "deadbeef";
     DWORD ret;
+    BOOL cdret;
 
-    ok(GetCurrentDirectoryA(sizeof(curdir), curdir) != 0, "Failed to get current dir err %d\n", GetLastError());
+    cdret = GetCurrentDirectoryA(sizeof(curdir), curdir);
+    ok(cdret, "Failed to get current dir err %d\n", GetLastError());
 
     /* Ignore .* extension */
     ofn.lStructSize = sizeof(ofn);