Merge Conflict Fix CL to lmp-mr1-release for ag/849478

DO NOT MERGE - libvpx: Pull from upstream

Current HEAD: 7105df53d7dc13d5e575bc8df714ec8d1da36b06

BUG=23452792

Change-Id: Ic78176fc369e0bacc71d423e0e2e6075d004aaec

 virtual void MismatchHook(const vpx_image_t *img1,
 const vpx_image_t *img2) {
 double mismatch_psnr = compute_psnr(img1, img2);
    mismatch_psnr_ += mismatch_psnr;
 ++mismatch_nframes_;
 }

 virtual void MismatchHook(const vpx_image_t *img1,
 const vpx_image_t *img2) {
 double mismatch_psnr = compute_psnr(img1, img2);
    mismatch_psnr_ += mismatch_psnr;
 ++mismatch_nframes_;
 }
