Dan Field fe30c3f235 [vm] Expose whether extension stream has listeners, guard postEvent ...

This avoids json encoding that was otherwise happening even in product mode. JSON encoding shows up CPU profiling as taking significant time, particularly on low end devices.

TEST=runtime/observatory/tests/service/developer_extension_test.dart

Bug: https://github.com/dart-lang/sdk/issues/48860
Change-Id: I2cf4d949e85c0b23de01ec2033b04527d40c76fe
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/242081
Reviewed-by: Ben Konyi <bkonyi@google.com>
Reviewed-by: Lasse Nielsen <lrn@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Commit-Queue: Dan Field <dnfield@google.com>

2022-04-26 07:53:43 +00:00

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entry_point_pragma.md

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