Reduce EventListenerVector's minimum capacity from 16 to 2 to save memory and get a small speedup on Speedometer. Very few event listeners are registered for a given type in the common case so eagerly allocating enough memory for 16 is wasteful. This is a confirmed 0.4% progression on Speedometer according to A/B bots.
Created attachment 455760 [details] Patch
Comment on attachment 455760 [details] Patch r=me
Committed r291866 (248872@main): <https://commits.webkit.org/248872@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 455760 [details].
<rdar://problem/90845294>