tree b18f983a02bcd617138e08d4e2f46288f9a83d4b
parent a5bf688622d4597e1cf1bd765a767c4045e157dd
author Paul Berry <paulberry@google.com> 1527277093 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1527277093 +0000

Observatory strong mode fixes: add explicit downcasts to button onClick callbacks.

Since the downcast is explicit (using "as") the type will be checked
even in unchecked mode, so technically there is a slight risk of
breakage.  But since the callback is so near the creation of the
ButtonElement, I'm not concerned.  Also, I'm not concerned about the
performance penalty of the explicit downcast because the cost is only
paid once per user click.

Change-Id: I64fbb442985f6ba6f745f665b36a3321498025e4
Reviewed-on: https://dart-review.googlesource.com/56704
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>