this -> address(this)

[BrendanChou]

Fixes #

Fixes errors in anticipation of Solidity 0.5.0

🚀 Description

• 📘 I've reviewed the OpenZeppelin Contributor Guidelines
• ✅ I've added tests where applicable to test my new functionality.
• 📖 I've made sure that my contracts are well-documented.
• 🎨 I've run the JS/Solidity linters and fixed any issues (npm run lint:all:fix).

[nventuro]

Hey @BrendanChou, thanks for this contribution!

I noticed there are some errors on our nightly build which seem related to this, we get these sorts of messages: TypeError: Return argument type contract SecureTargetMock is not implicitly convertible to expected type (type of first return variable) address.

Are those errors caused by this same issue, and if so, could you also address those? This is the nightly build for this PR, for reference: https://travis-ci.org/OpenZeppelin/openzeppelin-solidity/jobs/411415060

Thanks!

[nventuro]

I've updated the PR to target the solc-nightly branch.

[axic]

This should be backwards compatible and could be merged on master.

[nventuro]

@axic I'd rather have all of the 0.5.0 related changes into this branch, so that merging back to master is then as straightforward as possible.

Merging despite the build failing (for unrelated reasons).