"[dart:html] Move NullWindowException to implementation"
This is a revert of bd3e6fa1a3 and
2b250992f9.
This adds some small code change to avoid a null-assertion being emitted
that would lead to a browser SecurityError.
CoreLibraryReviewExempt: Reland.
Change-Id: Iab52bb728b14fd0b2378b8923b0e1ea8ea930b12
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/311922
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Commit-Queue: Srujan Gaddam <srujzs@google.com>
Srujan Gaddam
b859e00908