Lazier return in UnionType->isSuperTypeOf() (~40% faster)
          
            #18873
        
      | Job | Run time | 
|---|---|
| 29s | |
| 29s | |
| 25s | |
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| 38s | |
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| 37s | |
| 34s | |
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| 7m 35s | 
UnionType->isSuperTypeOf() (~40% faster)
          
            #18873
        
| Job | Run time | 
|---|---|
| 29s | |
| 29s | |
| 25s | |
| 27s | |
| 38s | |
| 25s | |
| 37s | |
| 34s | |
| 25s | |
| 38s | |
| 24s | |
| 37s | |
| 24s | |
| 37s | |
| 25s | |
| 1s | |
| 7m 35s |