[iOS/GN] Fix compilation of ios_chrome_unittests with gn.

build/config/arm.gni

 # Copyright 2014 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.
 
 if (current_cpu == "arm") {
   declare_args() {
     # Version of the ARM processor when compiling on ARM. Ignored on non-ARM
     # platforms.
     arm_version = 7
 
     # The ARM floating point mode. This is either the string "hard", "soft", or
     # "softfp". An empty string means to use the default one for the
     # arm_version.
     arm_float_abi = ""
 
     # The ARM variant-specific tuning mode. This will be a string like "armv6"
     # or "cortex-a15". An empty string means to use the default for the
     # arm_version.
     arm_tune = ""
 
     # Whether to use the neon FPU instruction set or not.
     arm_use_neon = true
 
     # Whether to enable optional NEON code paths.
     arm_optionally_use_neon = false
-
-    if (is_ios) {
-      arm_use_neon = false
-      arm_optionally_use_neon = false
-    }
   }
 
   assert(arm_float_abi == "" || arm_float_abi == "hard" ||
          arm_float_abi == "soft" || arm_float_abi == "softfp")
 
   if (arm_version == 6) {
     arm_arch = "armv6"
     if (arm_tune != "") {
       arm_tune = ""
     }
@@ skipping 24 matching lines @@
     if (arm_use_neon) {
       arm_fpu = "neon"
     } else {
       arm_fpu = "vfpv3-d16"
     }
   }
 } else if (current_cpu == "arm64") {
   # arm64 supports only "hard".
   arm_float_abi = "hard"
 }