Escape and Cmd+Enter (Ctrl+Enter on Windows and Linux) end text editing
and switch back to the tool that double-clicked into the type, or to the
Selection tool when there was none (`TypeTool::end_editing`). The
evidence lines in docs/type-parity.md, docs/ui-parity.md and
docs/target-app-parity.md, and the doc comments on `prev_tool` and
`claims_key`, said they always switch to the Selection tool.