Remove --assert-message VM flag

Remove --assert-message VM flag

Enable support for messages in assert statements. Remove the
VM flag.

BUG=#28136

Committed: https://github.com/dart-lang/sdk/commit/ef40b32e85c4e9af51ec12f06e92b39fc93db572

[hausner, 2016-12-19 20:21:00]

Description was changed from

==========
Remove --assert-message VM flag

Enable support for messages in assert statements. Remove the
VM flag.

BUG=#28136
==========

to

==========
Remove --assert-message VM flag

Enable support for messages in assert statements. Remove the
VM flag.

BUG=#28136
==========

[hausner, 2016-12-19 20:21:00]

hausner@google.com changed reviewers:
+ asiva@google.com

[hausner, 2016-12-19 23:23:16]

Description was changed from

==========
Remove --assert-message VM flag

Enable support for messages in assert statements. Remove the
VM flag.

BUG=#28136
==========

to

==========
Remove --assert-message VM flag

Enable support for messages in assert statements. Remove the
VM flag.

BUG=#28136

Committed:
https://github.com/dart-lang/sdk/commit/ef40b32e85c4e9af51ec12f06e92b39fc93db572
==========

[hausner, 2016-12-19 23:23:17]

Committed patchset #2 (id:20001) manually as
ef40b32e85c4e9af51ec12f06e92b39fc93db572 (presubmit successful).

[hausner, 2016-12-19 23:23:38]

TBR

[siva, 2016-12-19 23:27:37]

It appears that there are no tests for this feature as you
did not have to remove this flag from any of the tests.

How was this feature tested when the CL initially landed?

lgtm otherwise.

[hausner, 2016-12-20 00:22:49]

There is tests/language/assert_message_test.dart

It has a line SharedOptions=--assert-message in its comments. Because it's
shared with other compilers, I did not remove it.