T3064 regresses with wildcard refactor

This is to track a regression in the allocations of the T3064 compiler performance testcase as a result of Simon's wildcard refactoring (1e041b73),

=====> T3064(normal) 1 of 1 [0, 0, 0] 
cd ./perf/compiler &&  "/mnt/work/ghc/ghc-testing/inplace/test   spaces/ghc-stage2" -c T3064.hs -fforce-recomp -dno-debug-output -no-user-package-db -rtsopts -fno-warn-tabs -fno-warn-missed-specialisations -fno-ghci-history +RTS -G1 -RTS  +RTS -V0 -tT3064.comp.stats --machine-readable -RTS > T3064.comp.stderr 2>&1
bytes allocated value is too high:
    Expected    T3064(normal) bytes allocated: 243670824 +/-5%
    Lower bound T3064(normal) bytes allocated: 231487282 
    Upper bound T3064(normal) bytes allocated: 255854366 
    Actual      T3064(normal) bytes allocated: 264952256 
    Deviation   T3064(normal) bytes allocated:       8.7 %