Fix memory leak on cross thread events - #25783
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I believe that we started leaking the event data for cross-thread html5 events in emscripten-core#20370. Prior to that change we use `_emscripten_dispatch_to_thread` which took care of free'ing the event data once it was consumed on the target thread. After this change we copy make copy of the event strut in `_emscripten_run_callback_on_thread` and then free it once the callback is run. This change also avoid an extra malloc per event.
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I believe that we started leaking the event data for cross-thread html5 events in emscripten-core#20370. Prior to that change we use `_emscripten_dispatch_to_thread` which took care of free'ing the event data once it was consumed on the target thread. After this change we copy make copy of the event strut in `_emscripten_run_callback_on_thread` and then free it once the callback is run. This change also avoids an extra malloc per event, and cleans up libhtml5.js a little.
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In emscripten-core#25783 (80269bf), _emscripten_run_callback_on_thread was updated to take an event_data_size parameter. However, call sites passing 0 for event data in libhtml5.js and libhtml5_webgl.js were missed and left with 5 arguments instead of 6, causing userData to be passed as event_data_size and user_data to be omitted.
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…27264) In #25783, `_emscripten_run_callback_on_thread` was updated to take an event_data_size parameter. However, call sites passing 0 for event data in `libhtml5.js` and `libhtml5_webgl.js` were missed and left with 5 arguments instead of 6, causing `userData` to be passed as `event_data_size` and `user_data` to be omitted.
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I believe that we started leaking the event data for cross-thread html5 events in #20370.
Prior to that change we use
_emscripten_dispatch_to_threadwhich took care of free'ing the event data once it was consumed on the target thread.After this change we copy make copy of the event strut in
_emscripten_run_callback_on_threadand then free it once the callback is run.This change also avoids an extra malloc per event, and cleans up libhtml5.js a little.