Build changes for android on arm

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") {
+# Some components need arm settings for target_cpu too.

[brettw, 2015/03/16 17:16:36]

I think it would be good to make this more explicit. Something like

This file declares the ARM flags which are accessible when the current toolchain
is building for ARM, or the target toolchain is building for ARM.

+if (current_cpu == "arm" || target_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_android) {
+    if (is_android || target_os == "android") {
       arm_use_neon = false
       arm_optionally_use_neon = true
     }
   }
 
   assert(arm_float_abi == "" || arm_float_abi == "hard" ||
          arm_float_abi == "soft" || arm_float_abi == "softfp")
 
   if (arm_version == 6) {
     arm_arch = "armv6"
@@ skipping 20 matching lines @@
 
     arm_use_thumb = true
 
     if (arm_use_neon) {
       arm_fpu = "neon"
     } else {
       arm_fpu = "vfpv3-d16"
     }
   }
 }