[clang] [llvm] [WebAssembly] Implement an alternative translation for -wasm-enable-sjlj (PR #84137)

[YAMAMOTO Takashi via llvm-commits]

yamt wrote:

> i tried to run the relevant emscripten tests. but i have not succeeded yet even w/o these changes. (i'm an emscripten newbie.)

they passed with the latest version of this PR and the emscripten PR.



https://github.com/llvm/llvm-project/pull/84137