Roll src/third_party/libvpx/source/libvpx/ 91f87e751..4d4231352 (50 commits).

third_party/libvpx/source/config/linux/x64/vpx_dsp_rtcd.h

 #ifndef VPX_DSP_RTCD_H_
 #define VPX_DSP_RTCD_H_
 
 #ifdef RTCD_C
 #define RTCD_EXTERN
 #else
 #define RTCD_EXTERN extern
 #endif
 
 /*
@@ skipping 1084 matching lines @@
 void vpx_highbd_idct16x16_10_add_sse2(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct16x16_10_add vpx_highbd_idct16x16_10_add_sse2
 
 void vpx_highbd_idct16x16_1_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct16x16_1_add vpx_highbd_idct16x16_1_add_c
 
 void vpx_highbd_idct16x16_256_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 void vpx_highbd_idct16x16_256_add_sse2(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct16x16_256_add vpx_highbd_idct16x16_256_add_sse2
 
+void vpx_highbd_idct16x16_38_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
+void vpx_highbd_idct16x16_256_add_sse2(const tran_low_t *input, uint8_t *dest, int stride, int bd);
+#define vpx_highbd_idct16x16_38_add vpx_highbd_idct16x16_256_add_sse2
+
 void vpx_highbd_idct32x32_1024_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct32x32_1024_add vpx_highbd_idct32x32_1024_add_c
 
 void vpx_highbd_idct32x32_1_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 void vpx_highbd_idct32x32_1_add_sse2(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct32x32_1_add vpx_highbd_idct32x32_1_add_sse2
 
 void vpx_highbd_idct32x32_34_add_c(const tran_low_t *input, uint8_t *dest, int stride, int bd);
 #define vpx_highbd_idct32x32_34_add vpx_highbd_idct32x32_34_add_c
 
@@ skipping 1163 matching lines @@
     vpx_variance64x64 = vpx_variance64x64_sse2;
     if (flags & HAS_AVX2) vpx_variance64x64 = vpx_variance64x64_avx2;
 }
 #endif
 
 #ifdef __cplusplus
 }  // extern "C"
 #endif
 
 #endif