Enable AVX2 optimizations in libvpx

libvpx.gyp

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 {
   'variables': {
     'libvpx_build_vp9%': 1,
     'libvpx_source%': 'source/libvpx',
     # Disable LTO for neon targets
     # crbug.com/408997
     'use_lto%': 0,
@@ skipping 130 matching lines @@
               ],
               'dependencies': [
                 'libvpx_intrinsics_mmx',
                 'libvpx_intrinsics_sse2',
                 # Currently no sse3 intrinsic functions
                 #'libvpx_intrinsics_sse3',
                 'libvpx_intrinsics_ssse3',
                 'libvpx_intrinsics_sse4_1',
                 # Currently no avx intrinsic functions
                 #'libvpx_intrinsics_avx',
-                #'libvpx_intrinsics_avx2',
+                'libvpx_intrinsics_avx2',
               ],
             }],
             ['target_arch=="arm64"', {
               'includes': [ 'libvpx_srcs_arm64.gypi', ],
             }],
             ['target_arch=="x64"', {
               'conditions': [
                 ['msan==1', {
                   'includes': [ 'libvpx_srcs_generic.gypi', ],
                 }, {
                   'includes': [
                     'libvpx_srcs_x86_64.gypi',
                   ],
                   'dependencies': [
                     'libvpx_intrinsics_mmx',
                     'libvpx_intrinsics_sse2',
                     # Currently no sse3 intrinsic functions
                     #'libvpx_intrinsics_sse3',
                     'libvpx_intrinsics_ssse3',
                     'libvpx_intrinsics_sse4_1',
                     # Currently no avx intrinsic functions
                     #'libvpx_intrinsics_avx',
-                    #'libvpx_intrinsics_avx2',
+                    'libvpx_intrinsics_avx2',
                   ],
                 }],
               ],
             }],
           ],
         },
       ],
     },
     ],
     # 'libvpx' target for mipsel and mips64el builds.
@@ skipping 157 matching lines @@
                   '-fstack-protector-all',  # Implies -fstack-protector
                 ],
               },
             }],
           ],
         },
       ],
     }],
   ],
 }