Change code to determine ANSI support on Windows

Change code to determine ANSI support on Windows

R=ahe@google.com

Committed: https://github.com/dart-lang/sdk/commit/4d3719f54ebe5a50fd814d7be27b148a4c88a8e1

[karlklose, 2017-03-22 11:53:49]

karlklose@google.com changed reviewers:
+ ahe@google.com, zra@google.com

[ahe, 2017-03-22 12:05:36]

lgtm

https://codereview.chromium.org/2765223002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/colors.dart (right):

https://codereview.chromium.org/2765223002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/colors.dart:100: // implement `ansiSupported`.
ansiSupported -> supportsAnsiEscapes.

https://codereview.chromium.org/2765223002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/colors.dart:149: // ANSI escapes support is
hard-coded to true on non-Windows platforms.
It's no longer hard-code to true. This is more accurate:

To avoid linking the Dart VM with ncurses, ANSI escape support is reduced to
`Platform.environment['TERM'].contains("xterm")`.

[karlklose, 2017-03-22 12:20:52]

Description was changed from

==========
Change code to determine ANSI support on Windows
==========

to

==========
Change code to determine ANSI support on Windows

R=ahe@google.com

Committed:
https://github.com/dart-lang/sdk/commit/4d3719f54ebe5a50fd814d7be27b148a4c88a8e1
==========

[karlklose, 2017-03-22 12:20:53]

Committed patchset #2 (id:20001) manually as
4d3719f54ebe5a50fd814d7be27b148a4c88a8e1 (presubmit successful).