vp10: remove double MV value check.

This has virtually no effect on coding efficiency, but it is more
logical from a theoretical perspective (since it makes no sense to
me that you would exclude a MV from a list just because it's sign-
inversed value is identical to a value already in a list), and it
also makes the code simpler (it removes a duplicate value check in
cases where signbias is equal between the two MVs being compared).

See issue 662.

Change-Id: I23e607c6de150b9f11d1372fb2868b813c322d37

vp10/common/mvref_common.c

diff --git a/vp10/common/mvref_common.c b/vp10/common/mvref_common.c
index c0a8456..2678560 100644
--- a/vp10/common/mvref_common.c
+++ b/vp10/common/mvref_common.c
@@ -125,8 +125,10 @@
     }
 
     if (prev_frame_mvs->ref_frame[1] > INTRA_FRAME &&
-        prev_frame_mvs->ref_frame[1] != ref_frame &&
-        prev_frame_mvs->mv[1].as_int != prev_frame_mvs->mv[0].as_int) {
+#if !CONFIG_MISC_FIXES
+        prev_frame_mvs->mv[1].as_int != prev_frame_mvs->mv[0].as_int &&
+#endif
+        prev_frame_mvs->ref_frame[1] != ref_frame) {
       int_mv mv = prev_frame_mvs->mv[1];
       if (ref_sign_bias[prev_frame_mvs->ref_frame[1]] !=
           ref_sign_bias[ref_frame]) {

vp10/common/mvref_common.h

diff --git a/vp10/common/mvref_common.h b/vp10/common/mvref_common.h
index 8e918b8..0774f70 100644
--- a/vp10/common/mvref_common.h
+++ b/vp10/common/mvref_common.h
@@ -180,8 +180,9 @@
         ADD_MV_REF_LIST(scale_mv((mbmi), 0, ref_frame, ref_sign_bias), \
                         refmv_count, mv_ref_list, Done); \
       if (has_second_ref(mbmi) && \
-          (mbmi)->ref_frame[1] != ref_frame && \
-          (mbmi)->mv[1].as_int != (mbmi)->mv[0].as_int) \
+          (CONFIG_MISC_FIXES || \
+           (mbmi)->mv[1].as_int != (mbmi)->mv[0].as_int) && \
+          (mbmi)->ref_frame[1] != ref_frame) \
         ADD_MV_REF_LIST(scale_mv((mbmi), 1, ref_frame, ref_sign_bias), \
                         refmv_count, mv_ref_list, Done); \
     } \