diff -up firefox-46.0/media/webrtc/trunk/webrtc/build/common.gypi.arm firefox-46.0/media/webrtc/trunk/webrtc/build/common.gypi
--- firefox-46.0/media/webrtc/trunk/webrtc/build/common.gypi.arm	2016-04-25 12:03:12.486027089 +0200
+++ firefox-46.0/media/webrtc/trunk/webrtc/build/common.gypi	2016-04-25 12:05:55.714644873 +0200
@@ -312,20 +312,6 @@
         'defines': [
           'WEBRTC_ARCH_ARM',
         ],
-        'conditions': [
-          ['arm_version>=7', {
-            'defines': ['WEBRTC_ARCH_ARM_V7',
-                        'WEBRTC_BUILD_NEON_LIBS'],
-            'conditions': [
-              ['arm_neon==1', {
-                'defines': ['WEBRTC_ARCH_ARM_NEON',],
-              }],
-              ['arm_neon==0 and arm_neon_optional==1', {
-                'defines': ['WEBRTC_DETECT_ARM_NEON',],
-              }],
-            ],
-          }],
-        ],
       }],
       ['os_bsd==1', {
         'defines': [
diff -up firefox-51.0/gfx/skia/skia/include/core/SkPreConfig.h.old firefox-51.0/gfx/skia/skia/include/core/SkPreConfig.h
--- firefox-51.0/gfx/skia/skia/include/core/SkPreConfig.h.old	2017-01-20 10:22:48.921666380 +0100
+++ firefox-51.0/gfx/skia/skia/include/core/SkPreConfig.h	2017-01-20 10:23:23.600486691 +0100
@@ -208,6 +208,10 @@
     #define SK_ARM_HAS_NEON
 #endif
 
+#if defined(__aarch64__)
+    #undef SK_ARM_HAS_NEON
+#endif
+
 //////////////////////////////////////////////////////////////////////
 
 #if !defined(SKIA_IMPLEMENTATION)
diff -up firefox-51.0/media/webrtc/trunk/Makefile.old firefox-51.0/media/webrtc/trunk/Makefile