Fix setting editor with symbol

[srachner]

The changes in commit 6591cf9 broke setting an editor with a symbol, when the method Editor.for_symbol was renamed to Editor.editor_from_symbol.

[coveralls]

Pull Request Test Coverage Report for Build 347414729

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 96.838%

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Totals
Change from base Build 346475882:	0.0%
Covered Lines:	490
Relevant Lines:	506

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💛 - Coveralls

[RobinDaugherty]

Thank you! This should have been caught by rspec-mock! I'll cut a release for this right away and then investigate further.