Better toString and Error.toSafeString output for closures for dart2js.

Better toString and Error.toSafeString output for closures for dart2js.

Closures that appear in error messages, especially NoSuchMethodError, need to identify the function so that captured error messages and stack traces are useful.

Old:
  1. Instance of 'Object'
  2. Instance of 'Object'
  3. Instance of 'anonymous'
  4. Instance of 'anonymous'
  5. Instance of 'main_localFunction'

New:
  1. Closure 'print'
  2. Closure 'Widget_staticMethod'
  3. Closure 'foo' of Instance of 'Widget'
  4. Closure 'remainder' of 1234
  5. Closure 'main_localFunction'

In minified code the names are (usually) minified. Being able to unminify them later is separate issue.
This CL makes NoSuchMethodError variants more uniform in quoting of method to assist unminifying the message.

R=floitsch@google.com

Committed: https://code.google.com/p/dart/source/detail?r=45753

[sra1, 2015-05-12 21:30:24]

sra@google.com changed reviewers:
+ floitsch@google.com

[sra1, 2015-05-12 22:59:34]

Patchset #1 (id:1) has been deleted

[floitsch, 2015-05-12 23:14:16]

LGTM.

https://codereview.chromium.org/1138313002/diff/20001/sdk/lib/_internal/compi...
File sdk/lib/_internal/compiler/js_lib/core_patch.dart (right):

https://codereview.chromium.org/1138313002/diff/20001/sdk/lib/_internal/compi...
sdk/lib/_internal/compiler/js_lib/core_patch.dart:466: for (var argument in
_arguments) {
maybe?:
sb.writeAll(_arguments.map(Error.safeToString), ", ")
...
if (_nameArguments != null) {
  if (_arguments != null) sb.write(", ");

[sra1, 2015-05-12 23:25:50]

https://codereview.chromium.org/1138313002/diff/20001/sdk/lib/_internal/compi...
File sdk/lib/_internal/compiler/js_lib/core_patch.dart (right):

https://codereview.chromium.org/1138313002/diff/20001/sdk/lib/_internal/compi...
sdk/lib/_internal/compiler/js_lib/core_patch.dart:466: for (var argument in
_arguments) {
On 2015/05/12 23:14:16, floitsch wrote:
> maybe?:
> sb.writeAll(_arguments.map(Error.safeToString), ", ")
> ...
> if (_nameArguments != null) {
>   if (_arguments != null) sb.write(", ");
> 
if (_arguments != null && _arguments.isNotEmpty) ...

I has something like that but I was not quite happy with it.  I think this way
pulls in the fewest additional methods.

[sra1, 2015-05-12 23:47:31]

Committed patchset #1 (id:20001) manually as 45753 (presubmit successful).