Fix -Wshorten-64-to-32 in test-assembler-arm64.cc

Fix -Wshorten-64-to-32 in test-assembler-arm64.cc

The arm64 MacroAssembler expects buffer_size to be an unsigned, not a
size_t.

BUG=chromium:710913
Review-Url: https://codereview.chromium.org/2818513002
Cr-Commit-Position: refs/heads/master@{#44623}
Committed: https://chromium.googlesource.com/v8/v8/+/b2dc9230c14f3b1dd6e5231457a8d157c39b8489

[hans, 2017-04-12 17:27:53]

hans@chromium.org changed reviewers:
+ machenbach@chromium.org, marja@chromium.org

[hans, 2017-04-12 17:27:53]

Please take a look.

[hans, 2017-04-12 17:53:21]

The CQ bit was checked by hans@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-04-12 17:53:22]

Dry run: 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, 2017-04-12 18:12:30]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-04-12 18:12:31]

Dry run: This issue passed the CQ dry run.

[Michael Achenbach, 2017-04-12 18:41:48]

lgtm, thanks

[Michael Achenbach, 2017-04-12 18:42:45]

The CQ bit was checked by machenbach@chromium.org

[commit-bot: I haz the power, 2017-04-12 18:42:54]

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, 2017-04-12 18:44:27]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1492022565900270, "parent_rev":
"81bb72c11ce5bf506531390a09299f2244582db5", "commit_rev":
"b2dc9230c14f3b1dd6e5231457a8d157c39b8489"}

[commit-bot: I haz the power, 2017-04-12 18:44:33]

Description was changed from

==========
Fix -Wshorten-64-to-32 in test-assembler-arm64.cc

The arm64 MacroAssembler expects buffer_size to be an unsigned, not a
size_t.

BUG=chromium:710913
==========

to

==========
Fix -Wshorten-64-to-32 in test-assembler-arm64.cc

The arm64 MacroAssembler expects buffer_size to be an unsigned, not a
size_t.

BUG=chromium:710913

Review-Url: https://codereview.chromium.org/2818513002
Cr-Commit-Position: refs/heads/master@{#44623}
Committed:
https://chromium.googlesource.com/v8/v8/+/b2dc9230c14f3b1dd6e5231457a8d157c39...
==========

[commit-bot: I haz the power, 2017-04-12 18:44:34]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/b2dc9230c14f3b1dd6e5231457a8d157c39...