Implement more missing pieces in VM's core library. Although it does not seem to make sense to have…

Implement more missing pieces in VM's core library. Although it does not seem to make sense to have toStringAsFixed, toStringAsExponential and toStringAsPrecision in integers, the interface 'num' specifies them, most likely because of troubles in Javascript versions.
Note that Double_toStringAsExponential and Double_toStringAsPrecision are still unimplemented in C++. Instead of crashing, throw an exception. Also fix argument passing.
Committed: https://code.google.com/p/dart/source/detail?r=4463

[floitsch, 2012-02-22 09:40:33]

FYI:
https://chromiumcodereview.appspot.com/9113043/
http://code.google.com/p/dart/issues/detail?id=1327

Integer change LGTM (assuming that toDouble is accepted behavior).

[srdjan, 2012-02-22 15:19:50]

On 2012/02/22 09:40:33, floitsch wrote:
> FYI:
> https://chromiumcodereview.appspot.com/9113043/
> http://code.google.com/p/dart/issues/detail?id=1327
> 
> Integer change LGTM (assuming that toDouble is accepted behavior).

Reverted changes conflicting with Issue 9113043, leaving integer changes only.