only overwrite this in event handlers for custom events

[Rich-Harris]

fixes #1390

[codecov-io]

Codecov Report

Merging #1392 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1392      +/-   ##
==========================================
+ Coverage   91.25%   91.25%   +<.01%     
==========================================
  Files         122      122              
  Lines        4484     4485       +1     
  Branches     1384     1385       +1     
==========================================
+ Hits         4092     4093       +1     
  Misses        154      154              
  Partials      238      238

Impacted Files	Coverage Δ
src/compile/nodes/EventHandler.ts	100% <100%> (ø)	⬆️

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[Conduitry]

Oh, did I misunderstand you and think that you wanted to also hoist in more cases? Or, like me, did you just try hoisting, saw it broke stuff, and kick that one until later?

[Rich-Harris]

I think we should probably hoist in more cases (by default, except for custom events), but I reckon that's a 'when we get round to it' type thing. Leaving this as-is is always the correct thing to do for regular DOM events, regardless of hoisting, so I just made the minimal change that would fix the bug