…NFC]

This patch is the first patch in a series reworking of Pete Lawrence's
(@PortalPete) amazing proposal for better expression evaluator error
messages (https://github.com/llvm/llvm-project/pull/80938)

This patch is preparatory patch for improving the rendering of
expression evaluator diagnostics. Currently diagnostics are rendered
into a string and the command interpreter layer then textually parses
words like "error:" to (sometimes) color the output accordingly. In
order to enable user interfaces to do better with diagnostics, we need
to store them in a machine-readable fromat. This patch does this by
adding a new llvm::Error kind wrapping a DiagnosticDetail struct that
is used when the error type is eErrorTypeExpression. Multiple
diagnostics are modeled using llvm::ErrorList.

Right now the extra information is not used by the CommandInterpreter,
this will be added in a follow-up patch!

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.

that separates out language and version. To avoid reinventing the wheel
and introducing subtle incompatibilities, this API uses the table of
languages and versiond defined by the upcoming DWARF 6 standard
(https://dwarfstd.org/languages-v6.html). While the DWARF 6 spec is not
finialized, the list of languages is broadly considered stable.

The primary motivation for this is to allow the Swift language plugin to
switch between language dialects between, e.g., Swift 5.9 and 6.0 with
out introducing a ton of new language codes. On the main branch this
change is considered NFC.

Depends on https://github.com/llvm/llvm-project/pull/89980

StreamFile subclasses Stream (from lldbUtility) and is backed by a File
(from lldbHost). It does not depend on anything from lldbCore or any of its
sibling libraries, so I think it makes sense for this to live in
lldbHost instead.

Differential Revision: https://reviews.llvm.org/D157460

When trying to run an expression after a process has existed, you
currently are shown the following error message:

  (lldb) p strlen("")
  error: Can't make a function caller while the process is running

This error is wrong and pretty uninformative. After this patch, the
following error message is shown:

  (lldb) p strlen("")
  error: unable to evaluate expression while the process is exited: the
  process must be stopped because the expression might require
  allocating memory.

rdar://109731325

Differential revision: https://reviews.llvm.org/D151497

We generally prohibit this at a higher level - for instance requiring
the process to be stopped for "expr".  But when we trigger an expression
for internal purposes (e.g. to fetch types from the ObjC runtime) we weren't
checking the process state.  Now we explicitly check this at the very start
of the job so we don't get into bad states.

Differential Revision: https://reviews.llvm.org/D137684

LLVM includes this header unconditionally on all platforms
(including Windows), so this define should no longer be necessary.

No behavior change.

Differential Revision: https://reviews.llvm.org/D107338

The C headers are deprecated so as requested in D102845, this is replacing them
all with their (not deprecated) C++ equivalent.

Reviewed By: shafik

Differential Revision: https://reviews.llvm.org/D103084

LLDB uses utility functions to run code in the inferior for its own
internal purposes, such as reading classes from the Objective-C runtime
for example. Because these expressions should be transparent to the
user, we ignore breakpoints and unwind the stack on errors, which
makes them hard to debug.

This patch adds a new setting target.debug-utility-expression that, when
enabled, changes these options to facilitate debugging. It enables
breakpoints, disables unwinding and writes out the utility function
source code to disk so it shows up in the source view.

Differential revision: https://reviews.llvm.org/D97249

The UtilityFunction ctor was dropping the text argument. Probably for
that reason ClangUtilityFunction was setting the parent's member
directly instead of deferring to the parent ctor. Also change the
signatures to take strings which are std::moved in place.