Add extras test for calling into runtime.

Add extras test for calling into runtime.

The alternative of passing an object template at context creation is
unfeasible because we need a context to instantiate the template.
At the time we create the context from snapshot or bootstrap from
scratch, we would already need that template instance, leading to a
chicken-and-egg problem.

This is an alternative that is simpler and less intrusive.

R=domenic@chromium.org, jochen@chromium.org

Committed: https://crrev.com/bd219a760185fe59723c89e23ef357106fad473e
Cr-Commit-Position: refs/heads/master@{#28938}

[jochen (gone - plz use gerrit), 2015-06-11 11:42:54]

lgtm

[Yang, 2015-06-11 11:46:43]

The CQ bit was checked by yangguo@chromium.org

[commit-bot: I haz the power, 2015-06-11 11:46:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1182443002/1

[commit-bot: I haz the power, 2015-06-11 12:19:45]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-11 12:20:00]

Patchset 1 (id:??) landed as
https://crrev.com/bd219a760185fe59723c89e23ef357106fad473e
Cr-Commit-Position: refs/heads/master@{#28938}

[domenic, 2015-06-11 17:59:58]

On 2015/06/11 at 11:42:04, yangguo wrote:
> 

We may want to consider renaming "exports." I do not know what a good name would
be though.

I will update the design doc with this new pattern.

[domenic, 2015-06-11 18:08:05]

On 2015/06/11 at 17:59:58, domenic wrote:
> On 2015/06/11 at 11:42:04, yangguo wrote:
> > 
> 
> We may want to consider renaming "exports." I do not know what a good name
would be though.
> 
> I will update the design doc with this new pattern.

Design doc updated.
https://docs.google.com/document/d/1AT5-T0aHGp7Lt29vPWFr2-qG8r3l9CByyvKwEuA8E...

Maybe we could consider introducing two separate objects, exports and imports,
which are only differentiated by convention?

[Yang, 2015-06-12 08:56:54]

On 2015/06/11 18:08:05, domenic wrote:
> On 2015/06/11 at 17:59:58, domenic wrote:
> > On 2015/06/11 at 11:42:04, yangguo wrote:
> > > 
> > 
> > We may want to consider renaming "exports." I do not know what a good name
> would be though.
> > 
> > I will update the design doc with this new pattern.
> 
> Design doc updated.
>
https://docs.google.com/document/d/1AT5-T0aHGp7Lt29vPWFr2-qG8r3l9CByyvKwEuA8E...
> 
> Maybe we could consider introducing two separate objects, exports and imports,
> which are only differentiated by convention?

Or we could just rename it to "binding".