Handle uncaught error for warnIfSlow

[jiahaog]

Description

_warnIfSlow creates a new future that resolves after a timeout duration.

flutter/packages/flutter_driver/lib/src/driver/vmservice_driver.dart

Line 636 in 8568eda

return future..timeout(timeout, onTimeout: () { _log(message); return null; });

This is a new future that is separate from the returned future. If the original future resolves with an error, future.timeout will also complete with an error that cannot be handled by callers of _warnIfSlow.

This fixes the breakage of the recovery flow for health checks at

flutter/packages/flutter_driver/lib/src/driver/vmservice_driver.dart

Line 220 in 8568eda

if (e.code != error_code.METHOD_NOT_FOUND) {

.

Related Issues

None

Tests

I added the following tests:

Add a test to simulate a rpc failure.

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[jonahwilliams]

LGTM

This looks like a tricky bug, thank you for tracking it down.

[jiahaog]

No problem :)