Fix issue 2888.

Fix issue 2888.

Allow for the library tag handler to be setup for the isolate, instead of
while loading a script. This ensures that we can use #import on the boot strap libraries like builtin, uri etc.

This change results in a dart API change and corresponding modifications are
necessary in dartium and App Engine.
Committed: https://code.google.com/p/dart/source/detail?r=7506

[regis, 2012-05-03 21:35:29]

LGTM

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc
File bin/gen_snapshot.cc (right):

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc#newcode293
bin/gen_snapshot.cc:293: Dart_Handle result =
Dart_SetLibraryTagHandler(BuiltinLibraryTagHandler);
This declaration shadows the one above.

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc#newcode301
bin/gen_snapshot.cc:301: Dart_Handle library =
This declaration shadows the one above.

[siva, 2012-05-03 22:16:55]

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc
File bin/gen_snapshot.cc (right):

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc#newcode293
bin/gen_snapshot.cc:293: Dart_Handle result =
Dart_SetLibraryTagHandler(BuiltinLibraryTagHandler);
On 2012/05/03 21:35:30, regis wrote:
> This declaration shadows the one above.

Done.

http://codereview.chromium.org/10302020/diff/1/bin/gen_snapshot.cc#newcode301
bin/gen_snapshot.cc:301: Dart_Handle library =
On 2012/05/03 21:35:30, regis wrote:
> This declaration shadows the one above.

Done.

[Anton Muhin, 2012-05-04 10:38:11]

Siva,

it should be trivial to adjust Dartium code, the only problem is logistic: I am
leaving early today and we have holidays for the first half of the next week.

If you like, I can prepare a CL tomorrow (it's official business day over here).