Re-apply "Clean up the patch file for the isolate library by introducing a new buitlin library: iso…

Re-apply "Clean up the patch file for the isolate library by introducing a new buitlin library: isolate_helper.dart". This time load eagerly isolate_helper so that the native handler can see it.
Committed: https://code.google.com/p/dart/source/detail?r=16500

[ngeoffray, 2012-12-19 15:55:35]

TBR. This CL has already been reviewed in:

https://codereview.chromium.org/11574032/

and

https://codereview.chromium.org/11549017/

[ahe, 2012-12-19 16:22:46]

Why was it reverted, and how was the problem that caused the revert fixed?

[ngeoffray, 2012-12-19 16:25:48]

On 2012/12/19 16:22:46, ahe wrote:
> Why was it reverted, and how was the problem that caused the revert fixed?

It's mentioned in the description: "This time load eagerly isolate_helper so
that the native handler can see it". The problem was that the native handler
requires to see all native classes before doing any resolution. In the previous
CL, isolate_helper.dart was only loaded once we could see the program use
isolates.

[ahe, 2013-01-02 13:49:58]

On 2012/12/19 16:25:48, ngeoffray wrote:
> On 2012/12/19 16:22:46, ahe wrote:
> > Why was it reverted, and how was the problem that caused the revert fixed?
> 
> It's mentioned in the description: "This time load eagerly isolate_helper so
> that the native handler can see it". The problem was that the native handler
> requires to see all native classes before doing any resolution. In the
previous
> CL, isolate_helper.dart was only loaded once we could see the program use
> isolates.

What changes did you make? (files and lines, please).

How was the additional changes tested?

[ngeoffray, 2013-01-10 11:09:24]

On 2013/01/02 13:49:58, ahe wrote:
> On 2012/12/19 16:25:48, ngeoffray wrote:
> > On 2012/12/19 16:22:46, ahe wrote:
> > > Why was it reverted, and how was the problem that caused the revert fixed?
> > 
> > It's mentioned in the description: "This time load eagerly isolate_helper so
> > that the native handler can see it". The problem was that the native handler
> > requires to see all native classes before doing any resolution. In the
> previous
> > CL, isolate_helper.dart was only loaded once we could see the program use
> > isolates.
> 
> What changes did you make? (files and lines, please).
> 
> How was the additional changes tested?

The main change is in compiler.dart, scanBuiltinLibraries: we eagerly load the
isolate helper library instead of lazily because of the native handler. I will
try to find the regression test for the lazily loading version that used to
fail.