Fix null default value access (#29512).

Fix null default value access (#29512).

BUG=
R=brianwilkerson@google.com, scheglov@google.com

Fixes: #29512
Committed: https://github.com/dart-lang/sdk/commit/37dbc98df8ffd7f29caae37b662ff494dfa69de6

[pquitslund, 2017-04-28 18:19:12]

pquitslund@google.com changed reviewers:
+ brianwilkerson@google.com, scheglov@google.com

[Brian Wilkerson, 2017-04-28 18:20:26]

https://codereview.chromium.org/2844323004/diff/1/pkg/analysis_server/lib/src...
File pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
(right):

https://codereview.chromium.org/2844323004/diff/1/pkg/analysis_server/lib/src...
pkg/analysis_server/lib/src/services/completion/dart/utilities.dart:79: String
defaultValue = getDefaultStringParameterValue(param) ?? '';
Or just fix `getDefaultStringParameterValue` to never return `null`?

[pquitslund, 2017-04-28 18:24:25]

https://codereview.chromium.org/2844323004/diff/1/pkg/analysis_server/lib/src...
File pkg/analysis_server/lib/src/services/completion/dart/utilities.dart
(right):

https://codereview.chromium.org/2844323004/diff/1/pkg/analysis_server/lib/src...
pkg/analysis_server/lib/src/services/completion/dart/utilities.dart:79: String
defaultValue = getDefaultStringParameterValue(param) ?? '';
On 2017/04/28 18:20:26, Brian Wilkerson wrote:
> Or just fix `getDefaultStringParameterValue` to never return `null`?

We use `null` as a sentinel elsewhere (in arglist_contributor) where it's useful
to distinguish none from an empty string.

Might be worth consolidating approaches though...

I'll take a look a this as I'll be in the area working on Flutter `children:`
completions (https://github.com/flutter/flutter-intellij/issues/463).

[Brian Wilkerson, 2017-04-28 18:31:30]

In which case, lgtm

[scheglov, 2017-04-28 18:31:47]

lgtm

[pquitslund, 2017-04-28 18:33:39]

Description was changed from

==========
Fix null default value access (#29512).

BUG=

Fixes: #29512
==========

to

==========
Fix null default value access (#29512).

BUG=
R=brianwilkerson@google.com, scheglov@google.com

Fixes: #29512
Committed:
https://github.com/dart-lang/sdk/commit/37dbc98df8ffd7f29caae37b662ff494dfa69de6
==========

[pquitslund, 2017-04-28 18:33:40]

Committed patchset #1 (id:1) manually as
37dbc98df8ffd7f29caae37b662ff494dfa69de6 (presubmit successful).