Merge "Using stride (# of elements) instead of pitch (bytes) in fdct8x8."

diff --cc vp9/common/vp9_rtcd_defs.sh
Simple merge

diff --cc vp9/encoder/vp9_dct.c
Simple merge

diff --cc vp9/encoder/vp9_encodemb.c
Simple merge

diff --cc vp9/encoder/x86/vp9_dct_sse2.c
Simple merge