build.js records which emitted bundles contain src/shared/constants.js, and
constants.js carries a marker constant-folded from DEBUG itself. script/verify-build
cross-checks the two and fails on every way of not knowing, so deleting the
__BUILD_DEBUG__ define now breaks the build instead of shipping a live debug branch.
Runs the real popup in a pinned containerized Chrome and fails on any uncaught
page error or console.error. Also fixes the two defects it caught: the missing
showView import in addToken.js and the missing addressDotHtml import in
transactionDetail.js.
closes#150closes#151