Revert "Feature #909 proxy delegatecall"

[asaj]

Reverts #1152

This seems to have broken the end-to-end tests, which due to a yet-to-be-found bug in the incremental testing code, did not run when this PR was submitted.

The specific issue arises when trying to submit transactions before the registry implementation is deployed.

GetRegisteredAddressWithEvm returns evm: execution reverted rather than errors.ErrRegistryContractNotDeployed or errors.ErrSmartContractNotDeployed, because there is no code at the implementation address, which, with the changes in this PR, cause the call to fail.

https://github.com/celo-org/celo-blockchain/blob/master/core/vm/dynamic_params.go#L46

This causes us to fail to fetch the gas price minimum in tx_pool.go, and we reject the transaction.

https://github.com/celo-org/celo-blockchain/blob/master/core/tx_pool.go#L674

I recommend we first find and fix the bug in incremental testing, and then resubmit this PR along with an accompanying celo-blockchain PR that returns a different error when the call in GetRegisteredAddressWithEvm reverts, or possibly use a different proxy for the registry that doesn't include this check.

[codecov]

Codecov Report

Merging #1241 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1241   +/-   ##
=======================================
  Coverage   66.47%   66.47%           
=======================================
  Files         262      262           
  Lines        7648     7648           
  Branches      441      441           
=======================================
  Hits         5084     5084           
  Misses       2464     2464           
  Partials      100      100

Flag	Coverage Δ
#mobile	66.47% <ø> (ø)	⬆️

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[asaj]

Upon second glance, it seems like we would still have the same registry proxy code, since it's hard coded into the genesis block, which this PR didn't change. So I'm not totally sure why this seems to be causing issues.

If anything, I now would have thought that celo-org/celo-blockchain#507 would cause the issue. The story is a bit muddled by the end-to-end tests not being pointed to master during some of this time.

Still suggest we revert to get the end-to-end tests passing again.

[mrsmkl]

Seems like the problem is that at some point, the proxy contract is called before the implementationAddress has been set. After #1122, up-to-date proxy code is loaded into the genesis block when running e2e tests. (If you test locally, note that you have to build the contracts before running the test)