[gn] Switch android bots to gn

[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806
Committed: https://crrev.com/45fe9019bfe4054245a24ba4807df967a7b530c2
Cr-Commit-Position: refs/heads/master@{#39269}

[Michael Achenbach, 2016-09-08 09:42:46]

Description was changed from

==========
[gn] Switch android bots to gn

BUG=
==========

to

==========
[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806
==========

[Michael Achenbach, 2016-09-08 10:02:00]

machenbach@chromium.org changed reviewers:
+ jochen@chromium.org, vogelheim@chromium.org

[Michael Achenbach, 2016-09-08 10:02:00]

PTAL. Chrome's bump to version 12 has no gyp configurations anymore and
backporting the gn changes to gyp seems cumbersome:
https://codereview.chromium.org/2193943002

This bumps the ndk and switches our bots to gn (this also means that gyp on
android is broken from now on).

Comparisons:

arm:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Android%20Arm%20-%...

Stuff that stands out:
-DANDROID_BINSIZE_HACK
-DCR_CLANG_REVISION=280106-1
-DHAVE_OFF64_T
is all not used by v8 code.

-DANDROID_NDK_VERSION=r11c will change due to the bump.

-DCAN_USE_NEON is useful for making the snapshot as we support neon on all
devices where we test with these builds.

gn uses -fPIC instead of -fPIE for the files, which should be right for object
compilation. -fPIE will be used for linking only.

-mfloat-abi=softfp
-mfpu=neon
-mtune=generic-armv7-a

Should all fit to our devices.

arm64:
https://build.chromium.org/p/client.v8.ports/builders/V8%20Android%20Arm64%20...

Some of the above, but no additional surprises.

[jochen (gone - plz use gerrit), 2016-09-08 10:03:49]

lgtm

[Michael Achenbach, 2016-09-08 10:08:08]

The CQ bit was checked by machenbach@chromium.org

[commit-bot: I haz the power, 2016-09-08 10:08:10]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-08 10:30:49]

Description was changed from

==========
[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806
==========

to

==========
[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806
==========

[commit-bot: I haz the power, 2016-09-08 10:30:50]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-08 10:31:18]

Description was changed from

==========
[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806
==========

to

==========
[gn] Switch android bots to gn

Also roll build and android_tools, which contains a bump of
the ndk to r12b.

BUG=chromium:629806

Committed: https://crrev.com/45fe9019bfe4054245a24ba4807df967a7b530c2
Cr-Commit-Position: refs/heads/master@{#39269}
==========

[commit-bot: I haz the power, 2016-09-08 10:31:18]

Patchset 1 (id:??) landed as
https://crrev.com/45fe9019bfe4054245a24ba4807df967a7b530c2
Cr-Commit-Position: refs/heads/master@{#39269}