Fix GN arm64 build, add msan support in GN.

Fix GN arm64 build, add msan support.

The arm64 build is missing a few recently-added files.

Compiling with msan requires that v8 be compiled in arm64 mode. Hook this up.

Committed: https://crrev.com/89ff78f30886aaa866963edef4602fa258f94d5a
Cr-Commit-Position: refs/heads/master@{#30528}

[brettw, 2015-09-01 18:24:19]

brettw@chromium.org changed reviewers:
+ jochen@chromium.org

[brettw, 2015-09-01 21:25:58]

brettw@chromium.org changed reviewers:
+ adamk@chromium.org
- jochen@chromium.org

[brettw, 2015-09-01 21:25:59]

Jochen is out, Adam can you review?

[adamk, 2015-09-01 21:48:32]

https://codereview.chromium.org/1316233005/diff/1/BUILD.gn
File BUILD.gn (right):

https://codereview.chromium.org/1316233005/diff/1/BUILD.gn#newcode28
BUILD.gn:28: if (is_msan) {
Why is this arm64 only? My gyp-fu is weak, but I don't see a similar stanza in
the gyp files.

I'd appreciate a comment here, otherwise this looks like pure magic.

[brettw, 2015-09-01 21:59:52]

Good idea. I copied the comment from GYP. This is from common.gypi.

If you could help landing this, that would be great, I'm not a V8 committer as
far as I know.

[adamk, 2015-09-01 22:02:56]

Thanks, lgtm. The CQ should be able to land for you, let's give it a shot.

[adamk, 2015-09-01 22:02:58]

The CQ bit was checked by adamk@chromium.org

[commit-bot: I haz the power, 2015-09-01 22:03:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1316233005/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1316233005/20001

[brettw, 2015-09-01 22:12:16]

On 2015/09/01 22:03:13, commit-bot: I haz the power wrote:
> CQ is trying da patch. Follow status at
>  https://chromium-cq-status.appspot.com/patch-status/1316233005/20001
> View timeline at
>  https://chromium-cq-status.appspot.com/patch-timeline/1316233005/20001

Woah, that's new from last time I tried a v8 patch!

[commit-bot: I haz the power, 2015-09-01 23:05:26]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-09-01 23:05:34]

Patchset 2 (id:??) landed as
https://crrev.com/89ff78f30886aaa866963edef4602fa258f94d5a
Cr-Commit-Position: refs/heads/master@{#30528}