Fixed toString of Platform.environment on Windows

Fixed toString of Platform.environment on Windows

BUG= https://code.google.com/p/dart/issues/detail?id=19244
R=lrn@google.com

Committed: https://code.google.com/p/dart/source/detail?r=37192

[kevmoo, 2014-06-07 00:46:34]

Also includes cleanup to _CaseInsensitiveStringMap

[Lasse Reichstein Nielsen, 2014-06-07 12:49:41]

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dart
File sdk/lib/io/platform_impl.dart (right):

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dar...
sdk/lib/io/platform_impl.dart:92: class _CaseInsensitiveStringMap<V> extends
MapMixin<String, V> {
Extend MapBase instead of MapMixin.
It's silly to have both, but for consistency, we do.

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dar...
sdk/lib/io/platform_impl.dart:101: V remove(String key) =>
_map.remove(key.toUpperCase());
Remove should take an Object as argument, and just return null if it's not a
String.

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dar...
sdk/lib/io/platform_impl.dart:108: }
You would want to override putIfAbsent too, so it only does one lookup.
Same for containsKey and containsValue, so it doesn't use `keys.contains` and
(basically) `m.keys.map((v)=>m[v]).contains(value)`.

[Lasse Reichstein Nielsen, 2014-06-09 09:55:20]

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dart
File sdk/lib/io/platform_impl.dart (left):

https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dar...
sdk/lib/io/platform_impl.dart:124: }
If all of this is to just have a better toString, I would just add:

    String toString() => _map.toString();

Delegating to the underlying map is much better than having an extra map
implementation on top of a map.

We could then argue that DelegatingMap should be in dart:collection too, instead
of package:collection. It's like every useful feature we think of putting into a
package, we also start wanting in the core libraries. Can't have it all :(

[kevmoo, 2014-06-09 17:08:15]

On 2014/06/09 09:55:20, Lasse Reichstein Nielsen wrote:
> https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dart
> File sdk/lib/io/platform_impl.dart (left):
> 
>
https://codereview.chromium.org/325533002/diff/1/sdk/lib/io/platform_impl.dar...
> sdk/lib/io/platform_impl.dart:124: }
> If all of this is to just have a better toString, I would just add:
> 
>     String toString() => _map.toString();
> 
> Delegating to the underlying map is much better than having an extra map
> implementation on top of a map.
> 
> We could then argue that DelegatingMap should be in dart:collection too,
instead
> of package:collection. It's like every useful feature we think of putting into
a
> package, we also start wanting in the core libraries. Can't have it all :(

Since this is only used in one spot, I went w/ the simple impl you
recommended...with a bit of cleanup

PTAL

[Lasse Reichstein Nielsen, 2014-06-10 06:12:01]

lgtm

[kevmoo, 2014-06-10 18:37:13]

Committed patchset #2 manually as r37192 (presubmit successful).