Remove built in methods' function wrapper.

[st0012]

I removed the function wrapper for most class' built-in methods because they are marked as one of the hotspots when profiling. And for most cases, the wrapper function is unnecessary anyway.

[codecov]

Codecov Report

Merging #719 into master will decrease coverage by 0.28%.
The diff coverage is 87.16%.

@@            Coverage Diff             @@
##           master     #719      +/-   ##
==========================================
- Coverage   79.72%   79.44%   -0.29%     
==========================================
  Files          53       53              
  Lines        7355     7252     -103     
==========================================
- Hits         5864     5761     -103     
- Misses       1240     1244       +4     
+ Partials      251      247       -4

Impacted Files	Coverage Δ
vm/string.go	95.51% <ø> (-0.05%)	⬇️
vm/channel.go	88.46% <100%> (-1.2%)	⬇️
vm/boolean.go	91.3% <100%> (-1.01%)	⬇️
vm/concurrent_rw_lock.go	90.9% <100%> (-0.76%)	⬇️
vm/go_object.go	12.69% <15.38%> (-6.42%)	⬇️
vm/concurrent_array.go	76.92% <62.5%> (-2.03%)	⬇️
vm/integer.go	73.33% <66.66%> (-0.53%)	⬇️
vm/go_map.go	67.27% <71.42%> (-3.22%)	⬇️
vm/file.go	72.51% <74.33%> (-1.21%)	⬇️
vm/float.go	80.43% <78.88%> (-0.82%)	⬇️
... and 9 more

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[hachi8833]

I think the changes are nice!

[st0012]

@hachi8833 do you have time to help me rebase this? I'm afraid I might miss some of your changes if I do it myself 😓

[hachi8833]

OK, I'll look into it for rebasing.

[hachi8833]

Could you check #747 for the workaround of rebasing? @st0012

[hachi8833]

I think you can close the PR because #747 has been merged. Thanks! @st0012