test: input_decoder: add CC tests

The test is reliably failing with thread sanitizer enabled, without the
previous patches:

    ==================
    WARNING: ThreadSanitizer: data race (pid=242170)
      Write of size 8 at 0x7b6c00010088 by thread T10:
        #0 DecoderPlayCc ../../src/input/decoder.c:1008 (libvlccore.so.9+0xebbf5)
        #1 ModuleThread_QueueCc ../../src/input/decoder.c:1064 (libvlccore.so.9+0xec031)
        #2 decoder_QueueCc ../../include/vlc_codec.h:444 (test_src_input_decoder+0x5768)
        #3 decoder_decode_check_cc ../../test/src/input/decoder/input_decoder_scenarios.c:79 (test_src_input_decoder+0x5a4e)
        #4 DecoderDecode ../../test/src/input/decoder/input_decoder.c:90 (test_src_input_decoder+0x3dd4)
        #5 DecoderThread_DecodeBlock ../../src/input/decoder.c:1376 (libvlccore.so.9+0xed9f1)
        #6 DecoderThread_ProcessInput ../../src/input/decoder.c:1498 (libvlccore.so.9+0xee14a)
        #7 DecoderThread ../../src/input/decoder.c:1786 (libvlccore.so.9+0xef877)

      Previous read of size 1 at 0x7b6c00010088 by thread T8:
        #0 vlc_input_decoder_HasCCChanFlag ../../src/input/decoder.c:2445 (libvlccore.so.9+0xf2a2b)
        #1 vlc_input_decoder_SetCcState ../../src/input/decoder.c:2464 (libvlccore.so.9+0xf2b5f)
        #2 EsOutSelectEs ../../src/input/es_out.c:2446 (libvlccore.so.9+0x1095c4)
        #3 EsOutSelect ../../src/input/es_out.c:2686 (libvlccore.so.9+0x10a7fc)
        #4 EsOutVaControlLocked ../../src/input/es_out.c:3270 (libvlccore.so.9+0x10dea5)
        #5 EsOutControlLocked ../../src/input/es_out.c:3147 (libvlccore.so.9+0x10d0ae)
        #6 EsOutVaPrivControlLocked ../../src/input/es_out.c:3759 (libvlccore.so.9+0x112282)
        #7 EsOutPrivControl ../../src/input/es_out.c:4028 (libvlccore.so.9+0x11505c)
        #8 es_out_vaPrivControl ../../src/input/es_out.h:105 (libvlccore.so.9+0x125a49)
        #9 es_out_PrivControl ../../src/input/es_out.h:112 (libvlccore.so.9+0x125b38)
        #10 es_out_SetEs ../../src/input/es_out.h:124 (libvlccore.so.9+0x125c4b)
        #11 Control ../../src/input/input.c:2123 (libvlccore.so.9+0x130e15)
        #12 MainLoop ../../src/input/input.c:724 (libvlccore.so.9+0x129676)
        #13 Run ../../src/input/input.c:428 (libvlccore.so.9+0x127faa)