Build changes for android on arm

Build changes for android on arm

V8 wants to key off information about arm regardless of whether arm is
the host/target.
Added a couple of flags that icu want to set when building for arm
too.
These changes mirror the gyp side.

R=brettw@chromium.org
BUG=465456

[sky, 2015-03-09 20:18:42]

https://codereview.chromium.org/988183003/diff/1/build/secondary/third_party/...
File build/secondary/third_party/icu/BUILD.gn (right):

https://codereview.chromium.org/988183003/diff/1/build/secondary/third_party/...
build/secondary/third_party/icu/BUILD.gn:94: "source/i18n/coll.cpp",
I ran gn format on this and it changed around a bunch of stuff.

[sky, 2015-03-09 21:53:55]

I can't actually land this until I land
https://codereview.chromium.org/991023002 and
https://codereview.chromium.org/984353002/ . The latter I can land whenever, but
the former when rolled into chrome has to land at the same time as this...

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

https://codereview.chromium.org/988183003/diff/1/build/config/arm.gni
File build/config/arm.gni (right):

https://codereview.chromium.org/988183003/diff/1/build/config/arm.gni#newcode5
build/config/arm.gni:5: # Some components need arm settings for target_cpu too.
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.

https://codereview.chromium.org/988183003/diff/1/build/secondary/third_party/...
File build/secondary/third_party/icu/BUILD.gn (right):

https://codereview.chromium.org/988183003/diff/1/build/secondary/third_party/...
build/secondary/third_party/icu/BUILD.gn:36: (target_cpu == "arm" || target_cpu
== "ia32" || target_cpu == "mipsel") &&
I think everywhere here you have "target_cpu" you mean "current_cpu"

[sky, 2015-03-17 19:02:49]

This patch isn't needed, closing out.