Use bool, not int, for the 2nd test param row_mt_.

This should fix the following Visual Studio build failure:

C:\src\buildbot\test-libvpx\tests_aom\pusgKAqpIA\test\sb_multipass_test.cc(28):
warning C4800: 'const int': forcing value to bool 'true' or 'false'
(performance warning)

Change-Id: Ief2c7a43473120e640e7649022e199bae00cfbe1
diff --git a/test/sb_multipass_test.cc b/test/sb_multipass_test.cc
index bf7f66a..0ca76ab 100644
--- a/test/sb_multipass_test.cc
+++ b/test/sb_multipass_test.cc
@@ -20,8 +20,9 @@
 #include "test/yuv_video_source.h"
 
 namespace {
-class AV1SBMultipassTest : public ::libaom_test::CodecTestWith2Params<int, int>,
-                           public ::libaom_test::EncoderTest {
+class AV1SBMultipassTest
+    : public ::libaom_test::CodecTestWith2Params<int, bool>,
+      public ::libaom_test::EncoderTest {
  protected:
   AV1SBMultipassTest()
       : EncoderTest(GET_PARAM(0)), set_cpu_used_(GET_PARAM(1)),
@@ -147,6 +148,6 @@
 TEST_P(AV1SBMultipassTest, TwoPassMatchTest) { DoTest(); }
 
 AV1_INSTANTIATE_TEST_CASE(AV1SBMultipassTest, ::testing::Range(0, 6),
-                          ::testing::Range(0, 2));
+                          ::testing::Bool());
 
 }  // namespace