Fix incorrect fee math in MetaSwapUtils

[penandlim]

No description provided.

[codecov]

Codecov Report

Merging #469 (7b7060e) into master (6f37f97) will not change coverage.
The diff coverage is 0.00%.

@@          Coverage Diff           @@
##           master    #469   +/-   ##
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  Coverage    0.00%   0.00%           
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  Files          15      15           
  Lines         982     994   +12     
  Branches      137     139    +2     
======================================
- Misses        982     994   +12     

Impacted Files	Coverage Δ
contracts/meta/MetaSwapUtils.sol	0.00% <0.00%> (ø)

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[hermitsgame]

#470
@penandlim @alphastorm

[penandlim]

@hermitsgame Nice catch!
Looks like we can scale dyFee the same way we scale v.dy here

saddle-contract/contracts/meta/MetaSwapUtils.sol

Lines 824 to 829 in b00cdec

	if (tokenIndexTo >= baseLPTokenIndex) {
	// When swapping to a base Swap token, scale down dy by its virtual price
	v.dy = v.dy.mul(BASE_VIRTUAL_PRICE_PRECISION).div(
	v.baseVirtualPrice
	);
	}

Thoughts? @ChiTimesChi