Skip tests that we expect won't work on MSVC.

c++/src/capnp/endian-reverse-test.c++

@@ -19,6 +19,10 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 // THE SOFTWARE.
 
+#if !_MSC_VER
+// (MSVC targets only little-endian platforms and so we haven't implemented any byte swapping
+// intrinsics for it. So, this test would fail there.)
+
 // Test that the code for the opposite endianness of our CPU works.  E.g. on x86 this will test
 // the bswap-based code.
 #define CAPNP_REVERSE_ENDIAN 1
@@ -104,3 +108,5 @@ TEST(EndianReverse, EightBytes) {
 }  // namespace
 }  // namespace _ (private)
 }  // namespace capnp
+
+#endif  // !_MSC_VER

c++/src/kj/async-test.c++

@@ -26,9 +26,12 @@
 namespace kj {
 namespace {
 
+#if !_MSC_VER
+// TODO(msvc): GetFunctorStartAddress is not supported on MSVC currently, so skip the test.
 TEST(Async, GetFunctorStartAddress) {
   EXPECT_TRUE(nullptr != _::GetFunctorStartAddress<>::apply([](){return 0;}));
 }
+#endif
 
 TEST(Async, EvalVoid) {
   EventLoop loop;