fix[ReactDevTools]: wrap sendMessage expressions in setTimeout

[hoxyq]

Summary

See https://fburl.com/workplace/zt1bzqky for full context. This is a mitigation to make highlighting work, until the root cause is fixed.

Test plan

Before:

before.mov

After:

after.mov

Upstreaming plan

• This commit should be sent as a patch to the upstream devtools-frontend repo. I've reviewed the contribution guide.
• This commit is React Native-specific and cannot be upstreamed.

[huntie]

Thanks for mitigating this so quickly 🙏🏻