Fix compilation for Opera.

Fix compilation for Opera.

2 issues:
- Opera claims to support __proto__ but for some cases it is buggy: it can happen that the changing of __proto__ makes the object lose fields.
- Opera sometimes returns "Function.prototype" for the 'name'-property of the constructor of DOM objects.

The first issue is fixed with a supportsProtoCheck. To do this, I slightly refactored the defineClass method, so it doesn't have a side-effect (except for the arguments that are passed in).
This also made it necessary to use the "new" syntax for BoundClosure classes: $$.BoundClosure = { ... };
Normally this is nicer anyways. The only problem could be that I missed a case where we generate a bound closure and do not call "finishClasses" afterwards.

Fixes issue 3812.

Committed: https://code.google.com/p/dart/source/detail?r=9736

[vsm, 2012-07-18 05:33:31]

LGTM!  Can you add a test?  I added a short one to the bug.

https://chromiumcodereview.appspot.com/10781019/diff/1/lib/compiler/implement...
File lib/compiler/implementation/emitter.dart (right):

https://chromiumcodereview.appspot.com/10781019/diff/1/lib/compiler/implement...
lib/compiler/implementation/emitter.dart:133: // On
Delete last line.

[floitsch, 2012-07-18 12:19:33]

I'm not completely sure how to add an Opera test.
I will commit this CL, and then we can discuss how to add the test(s) offline.

https://chromiumcodereview.appspot.com/10781019/diff/1/lib/compiler/implement...
File lib/compiler/implementation/emitter.dart (right):

https://chromiumcodereview.appspot.com/10781019/diff/1/lib/compiler/implement...
lib/compiler/implementation/emitter.dart:133: // On
On 2012/07/18 05:33:31, vsm wrote:
> Delete last line.

Done.