dart2js: make type tests fully use interceptors

[rakudrama]

Several places have this pattern of type test:

(typeof x == "function" ? x : $.getInterceptor(x)).$isFooCallback()

The root cause is Issue #9586.
Once 9586 is fixed, we should be able replace the above with:

$.getInterceptor(x).$isFooCallback()

[rakudrama]

Marked this as blocking #9728.

[rakudrama]

Marked this as blocking #9731.

[rakudrama]

Marked this as blocking #9732.

[kasperl]

Added this to the Later milestone.

[kasperl]

Added TriageForM5 label.

[kasperl]

Removed TriageForM5 label.

[kasperl]

Assigning to Nicolas to get a feel for how quickly this can be addressed.

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Set owner to [email protected].
Removed this from the Later milestone.
Added this to the M8 milestone.

[DartBot]

This comment was originally written by [email protected]

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This was fixed for a long time, we create a HInterceptor ssa node that gets removed by the SSA optimizers if the type check does not need it.

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Added Fixed label.