Delete Reactor/DebugAndroid.cpp and Reactor/DebugAndroid.hpp for the same reasons explained in the parent change.

The System / Reactor debug implementations are still not merged, but at least they're now consistent.
System/Debug requires `UNIMPLEMENTED()` to have a bug number for each message, but reactor has a whole bunch of ancient uses without any mention of a bug. I don't have the context to create these bugs, so for now I've created a temporary `UNIMPLEMENTED_NO_BUG()` variant. With this we can easily grep the codebase to locate these usages and create bugs as needed.

Bug: b/146051794
Bug: b/144093703
Change-Id: Id5208f924e63dae7443f95aab5b601a290c297e7
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/40969
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Ben Clayton <bclayton@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>