This was originally added so you could use "break on caught exceptions"
but that feature is pretty useless these days since it's used for feature
detection and Suspense.
The better pattern is to use the stack trace, jump to source and set a
break point here.
Since DevTools injects its own console.error, we could inject a "debugger"
statement in there. Conditionally. E.g. React DevTools could have a flag
to toggle "break on warnings".
* Detect double stacks in the new format in tests
* Remove unnecessary uses of getStackByFiberInDevAndProd
These all execute in the right execution context already.
* Set the debug fiber around the cases that don't have an execution context
* Remove stack detection in our console log overrides
We never pass custom stacks as part of the args anymore.
* Bonus: Don't append getStackAddendum to invariants
We print component stacks for every error anyway so this is just duplicate
information.
* Replace all warning/lowPriWarning with console calls
* Replace console.warn/error with a custom wrapper at build time
* Fail the build for console.error/warn() where we can't read the stack
