Add a 1x1 enc/dec test.

Change-Id: I777f49a3c2c2aaa04ae23904396bd7254e1afd8c
diff --git a/test/frame_size_tests.cc b/test/frame_size_tests.cc
index 1c9a522..95cc66a 100644
--- a/test/frame_size_tests.cc
+++ b/test/frame_size_tests.cc
@@ -84,4 +84,13 @@
   ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
 #endif
 }
+
+TEST_F(VP9FrameSizeTestsLarge, OneByOneVideo) {
+  ::libvpx_test::RandomVideoSource video;
+
+  video.SetSize(1, 1);
+  video.set_limit(2);
+  expected_res_ = VPX_CODEC_OK;
+  ASSERT_NO_FATAL_FAILURE(RunLoop(&video));
+}
 }  // namespace