fix(toolbar): solves NgUpgrade interop issue. Fixes #6069

[alex94cp]

I know development is currently focused on ng2, but these changes are so minor it can't hurt

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[alex94cp]

I signed it!

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CLAs look good, thanks!

[alex94cp]

PR now passes all tests. It depends on angular/angular#5604

[ThomasBurleson]

@jelbourn - Seems like something to have before our v1.0.0 release. thoughts ?

[jelbourn]

LGTM, this is fine