R=fbarchard@google.com
BUG=libyuv:634

Performance Gain (vs C vectorized)
ARGB1555ToARGBRow_MSA     - 1.85
ARGB1555ToARGBRow_Any_MSA - 1.82
RGB565ToARGBRow_MSA       - 2.14
RGB565ToARGBRow_Any_MSA   - 2.08
RGB24ToARGBRow_MSA        - 8.57
RGB24ToARGBRow_Any_MSA    - 7.42
RAWToARGBRow_MSA          - 8.57
RAWToARGBRow_Any_MSA      - 7.42
ARGB1555ToYRow_MSA        - 2.60
ARGB1555ToYRow_Any_MSA    - 2.47
RGB565ToYRow_MSA          - 2.45
RGB565ToYRow_Any_MSA      - 2.33
RGB24ToYRow_MSA           - 2.23
RGB24ToYRow_Any_MSA       - 2.01
RAWToYRow_MSA             - 2.25
RAWToYRow_Any_MSA         - 2.02
ARGB1555ToUVRow_MSA       - 1.40
ARGB1555ToUVRow_Any_MSA   - 1.37
RGB565ToUVRow_MSA         - 1.68
RGB565ToUVRow_Any_MSA     - 1.63
RGB24ToUVRow_MSA          - 3.02
RGB24ToUVRow_Any_MSA      - 2.87
RAWToUVRow_MSA            - 3.04
RAWToUVRow_Any_MSA        - 2.85

Performance Gain (vs C non-vectorized)
ARGB1555ToARGBRow_MSA     - 4.66
ARGB1555ToARGBRow_Any_MSA - 4.45
RGB565ToARGBRow_MSA       - 5.58
RGB565ToARGBRow_Any_MSA   - 5.34
RGB24ToARGBRow_MSA        - 8.57
RGB24ToARGBRow_Any_MSA    - 7.42
RAWToARGBRow_MSA          - 8.57
RAWToARGBRow_Any_MSA      - 7.42
ARGB1555ToYRow_MSA        - 6.38
ARGB1555ToYRow_Any_MSA    - 5.98
RGB565ToYRow_MSA          - 6.42
RGB565ToYRow_Any_MSA      - 6.05
RGB24ToYRow_MSA           - 7.87
RGB24ToYRow_Any_MSA       - 7.01
RAWToYRow_MSA             - 7.98
RAWToYRow_Any_MSA         - 7.01
ARGB1555ToUVRow_MSA       - 5.39
ARGB1555ToUVRow_Any_MSA   - 5.06
RGB565ToUVRow_MSA         - 6.39
RGB565ToUVRow_Any_MSA     - 5.90
RGB24ToUVRow_MSA          - 3.04
RGB24ToUVRow_Any_MSA      - 2.87
RAWToUVRow_MSA            - 3.04
RAWToUVRow_Any_MSA        - 2.88

Review-Url: https://codereview.chromium.org/2600713002 .