feat: add an option to translate JS_IR with DCE.#501

JSMonk wants to merge 2 commits intoJetBrains:masterJetBrains/kotlin-compiler-server:masterfrom

JSMonk:add-dce-flag-for-js-ir-compilationJSMonk/kotlin-compiler-server:add-dce-flag-for-js-ir-compilationCopy head branch name to clipboard