When we restart a process, send an updated 'process' event describing
the newly launched process.

I also updated the `isLocalProcess` value based on if we're on the
'host' platform or not.

A few files of lldb dir & few other files had duplicate headers
included. This patch removes those redundancies.

---------

Co-authored-by: Akash Agrawal <akashag@qti.qualcomm.com>

This patch removes all of the Set.* methods from Status.

This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.

This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()

Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form

`    ResultTy DoFoo(Status& error)
`
to

`    llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?

The interesting changes are in Status.h and Status.cpp, all other
changes are mostly

` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.

Add the ability to list all processes through the SB API.

rdar://116188959

Expose Platform::Attach through the SB API.

rdar://116188959

RFC https://discourse.llvm.org/t/rfc-python-callback-for-target-get-module/71580

Use SWIG for the locate module callback the same as other Python callbacks.
TestLocateModuleCallback.py verifies the functionalities.

Differential Revision: https://reviews.llvm.org/D153735

If you pass `nullptr` (or `None` from python) to SBPlatform::SetSDKRoot,
LLDB crashes. Let's be more resilient to `nullptr` here.

Differential Revision: https://reviews.llvm.org/D152962

These don't need to be ConstStrings. They don't really benefit much from
deduplication and comparing them isn't on a hot path, so they don't
really benefit much from quick comparisons.

Differential Revision: https://reviews.llvm.org/D152331

LLDB should guarantee that the strings returned by SBAPI methods
live forever. I went through every method that returns a string and made
sure that it was added to the ConstString StringPool before returning if
it wasn't obvious that it was already doing so.
I've also updated the docs to document this behavior.

Differential Revision: https://reviews.llvm.org/D150804