Formatter line continuation awareness hooks.

Formatter line continuation awareness hooks.

DO indent continued lines with at least four spaces.

https://www.dartlang.org/articles/style-guide/#do-indent-continued-lines-with-at-least-four-spaces

NOTE: these are just the hooks.  As per our conversations, we need to encode opinions about what continuations should be allowed before we support them.  The tests are left, commented out, to serve as tracer bullets when we get there.

R=brianwilkerson@google.com

Committed: https://code.google.com/p/dart/source/detail?r=31210

[Brian Wilkerson, 2013-12-13 22:38:03]

LGTM

https://codereview.chromium.org/109423004/diff/1/pkg/analyzer/lib/src/service...
File pkg/analyzer/lib/src/services/formatter_impl.dart (right):

https://codereview.chromium.org/109423004/diff/1/pkg/analyzer/lib/src/service...
pkg/analyzer/lib/src/services/formatter_impl.dart:1349: indent(2);
Do we want to increase the indentation if allowContinuedLines is called
recursively? For example, we call it both in an assignment expression and in a
conditional expression, so the indent will be N + 4 while processing the 'then'
and 'else' conditions in the following:

  a = b ? c : d;

[pquitslund, 2013-12-17 22:17:51]

Updated to remove actual handling, leaving only the hooks for future filling in.

[Brian Wilkerson, 2013-12-17 22:20:29]

LGTM

[pquitslund, 2013-12-17 22:38:41]

Committed patchset #3 manually as r31210 (presubmit successful).