Fix possible leaks in CanvasContext HintSessionWrapper Ensure the mHintSessionFuture is accounted for correctly in the destructor. Bug: b/297230599 Test: manual Change-Id: Idcbd0f2ba87290f090d693f0a64cb46fe8270b95 Merged-In: Idcbd0f2ba87290f090d693f0a64cb46fe8270b95 (cherry picked from commit ac620f64a32500890007b0b405ca72405d6db41e)