vp10: remove clamp_mv2() call from vp10_find_best_ref_mvs().

This actually has no effect whatsoever, since the input MVs themselves
are clamped by clamp_mv_ref() already, which is significantly more
restrictive in its bounds.

Change-Id: I4a3a7b2b121ee422c56428c2a12d930c3813c06e

vp10/encoder/rdopt.c

diff --git a/vp10/encoder/rdopt.c b/vp10/encoder/rdopt.c
index e3bbdd3..3aeb9b3 100644
--- a/vp10/encoder/rdopt.c
+++ b/vp10/encoder/rdopt.c
@@ -2142,9 +2142,9 @@
                    NULL, NULL, mbmi_ext->mode_context);
 
   // Candidate refinement carried out at encoder and decoder
-  vp10_find_best_ref_mvs(xd, cm->allow_high_precision_mv, candidates,
-                        &frame_nearest_mv[ref_frame],
-                        &frame_near_mv[ref_frame]);
+  vp10_find_best_ref_mvs(cm->allow_high_precision_mv, candidates,
+                         &frame_nearest_mv[ref_frame],
+                         &frame_near_mv[ref_frame]);
 
   // Further refinement that is encode side only to test the top few candidates
   // in full and choose the best as the centre point for subsequent searches.
@@ -2315,6 +2315,18 @@
            (mode_mv[NEARMV][ref_frame].as_int == INVALID_MV)));
 }
 
+#define LEFT_TOP_MARGIN ((VP9_ENC_BORDER_IN_PIXELS - VP9_INTERP_EXTEND) << 3)
+#define RIGHT_BOTTOM_MARGIN ((VP9_ENC_BORDER_IN_PIXELS -\
+                                VP9_INTERP_EXTEND) << 3)
+
+// TODO(jingning): this mv clamping function should be block size dependent.
+static INLINE void clamp_mv2(MV *mv, const MACROBLOCKD *xd) {
+  clamp_mv(mv, xd->mb_to_left_edge - LEFT_TOP_MARGIN,
+               xd->mb_to_right_edge + RIGHT_BOTTOM_MARGIN,
+               xd->mb_to_top_edge - LEFT_TOP_MARGIN,
+               xd->mb_to_bottom_edge + RIGHT_BOTTOM_MARGIN);
+}
+
 static int64_t handle_inter_mode(VP10_COMP *cpi, MACROBLOCK *x,
                                  BLOCK_SIZE bsize,
                                  int *rate2, int64_t *distortion,