Description

Saw a crash report this morning that showed that _checkDisposed was throwing a StateError within _decodeNextFrameAndSchedule.

Related Issue

Tests

I added the following tests:

• Test that ensures there is no error thrown when an image finishes decoding after there are no listeners.
• Updated test since transient callbacks are no longer registered after an image finishes decoding when there are no listeners. Before this change, another app frame would be scheduled, but that app frame does nothing.

Checklist

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• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I signed the CLA.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.
• The analyzer (flutter analyze --flutter-repo) does not report any problems on my PR.
• I am willing to follow-up on review comments in a timely manner.

Breaking Change

Did any tests fail when you ran them? Please read Handling breaking changes.

• No, no existing tests failed, so this is not a breaking change.
• Yes, this is a breaking change. If not, delete the remainder of this section.
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