fate: add chroma position scale test

The sample position is made weird and non-nominal to force catching
such issues as default values or specialized operations hiding
issues in corner cases.
Signed-off-by: NMichael Niedermayer <michael@niedermayer.cc>

tests/fate/filter-video.mak

@@ -349,6 +349,10 @@ fate-filter-scale200: CMD = video_filter "scale=w=200:h=200"
 FATE_FILTER_VSYNTH-$(CONFIG_SCALE_FILTER) += fate-filter-scale500
 fate-filter-scale500: CMD = video_filter "scale=w=500:h=500"
 
+FATE_FILTER_VSYNTH-$(CONFIG_SCALE_FILTER) += fate-filter-scalechroma
+fate-filter-scalechroma: tests/data/vsynth1.yuv
+fate-filter-scalechroma: CMD = framecrc -flags bitexact -s 352x288 -pix_fmt yuv444p -i tests/data/vsynth1.yuv -pix_fmt yuv420p -sws_flags +bitexact -vf scale=out_v_chr_pos=33:out_h_chr_pos=151
+
 FATE_FILTER_VSYNTH-$(CONFIG_VFLIP_FILTER) += fate-filter-vflip
 fate-filter-vflip: CMD = video_filter "vflip"
 

tests/ref/fate/filter-scalechroma

+#tb 0: 1/25
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