Add MapBasedTaskInput.

Add MapBasedTaskInput.

I found out that I'm blocked by its absence.
To resolve directives (actually to report errors) I need to know source kinds.
And the only way to get the SourceKind of a Source is to request a Map-based input.

If you have already implemented it yourself, feel free to upload your CL instead.
I'm not too much attached to this implementation :-)

R=brianwilkerson@google.com
BUG=

Committed: https://code.google.com/p/dart/source/detail?r=44429

[Brian Wilkerson, 2015-03-12 13:59:47]

LGTM

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
File pkg/analyzer/lib/src/task/inputs.dart (right):

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:348: * another (base) task input is used
to compute a [List]-valued result. An input
The comment needs to be updated.

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:353: abstract class
_CollectionBasedTaskInput<B, E, C> implements TaskInput<C> {
Is there a reason to make this class private? (It's ok to make it private
without a good reason, just curious.)

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:363: GenerateTaskInputs<E>
generateTaskInputs;
Should this be final?

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:375: * A [TaskInputBuilder] used to build
an input based on a [ListBasedTaskInput].
The comment needs to be updated.

[scheglov, 2015-03-12 15:10:36]

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
File pkg/analyzer/lib/src/task/inputs.dart (right):

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:348: * another (base) task input is used
to compute a [List]-valued result. An input
On 2015/03/12 13:59:47, Brian Wilkerson wrote:
> The comment needs to be updated.

Actually baseAccessor still provides a List.

But results of *this* input can be any collections.

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:353: abstract class
_CollectionBasedTaskInput<B, E, C> implements TaskInput<C> {
On 2015/03/12 13:59:47, Brian Wilkerson wrote:
> Is there a reason to make this class private? (It's ok to make it private
> without a good reason, just curious.)

I don't think there is  lot of different data structures that could be useful as
task inputs.
So, if this library provides all of them, there is no reason to open any
intermediate classes.

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:363: GenerateTaskInputs<E>
generateTaskInputs;
On 2015/03/12 13:59:47, Brian Wilkerson wrote:
> Should this be final?

Done.

https://codereview.chromium.org/997383002/diff/1/pkg/analyzer/lib/src/task/in...
pkg/analyzer/lib/src/task/inputs.dart:375: * A [TaskInputBuilder] used to build
an input based on a [ListBasedTaskInput].
On 2015/03/12 13:59:47, Brian Wilkerson wrote:
> The comment needs to be updated.

Done.

[scheglov, 2015-03-12 15:11:52]

Committed patchset #2 (id:20001) manually as 44429 (presubmit successful).