Remove runtime NEON detection

webrtc/build/common.gypi

Index: webrtc/build/common.gypi
diff --git a/webrtc/build/common.gypi b/webrtc/build/common.gypi
index f8446d9f91bce9e16aa52cd9dfc5df9ae293007e..42e8e54a401db9ebfd5e41d35db25be97db5b629 100644
--- a/webrtc/build/common.gypi
+++ b/webrtc/build/common.gypi
@@ -209,7 +209,7 @@
       ['target_arch=="arm" or target_arch=="arm64" or target_arch=="mipsel"', {
         'prefer_fixed_point%': 1,
       }],
-      ['(target_arch=="arm" and (arm_neon==1 or arm_neon_optional==1)) or target_arch=="arm64"', {
+      ['(target_arch=="arm" and arm_neon==1) or target_arch=="arm64"', {
         'build_with_neon%': 1,
       }],
       ['OS!="ios" and (target_arch!="arm" or arm_version>=7) and target_arch!="mips64el"', {
@@ -334,9 +334,6 @@
               ['arm_neon==1', {
                 'defines': ['WEBRTC_HAS_NEON',],
               }],
-              ['arm_neon==0 and arm_neon_optional==1', {
-                'defines': ['WEBRTC_DETECT_NEON',],
-              }],
             ],
           }],
         ],