For bad input data, the decoder may access the array out of bounds. The
commit added clamp to prevent such out of bound access
Change-Id: I0a1cfd9b8786ea7113a998053c76605c963b077a
Values of MODE_UPDATE_PROB and VP9_COEF_UPDATE_PROB are equal, so replacing
them with one constant. Inlining appropriate arguments for functions:
vp9_cond_prob_diff_update (encoder)
vp9_diff_update_prob (decoder)
Change-Id: I1255a1cb477743b799b3bfbbcd8de6b32b067338
Uses mapping tables instead of complicated modulo/division
operations for prob mapping for forward updates.
No bit-stream or output change.
Change-Id: Ifd9ce8ac1437835c305c94f64c18273c7a68f546
