The original PR is #132274.

Co-authored-by: @bulbazord Alex Langford

Reverts llvm/llvm-project#132274

Broke a test on LLDB Widows on Arm:
https://lab.llvm.org/buildbot/#/builders/141/builds/7726
```
FAIL: test_dwarf (lldbsuite.test.lldbtest.TestExternCSymbols.test_dwarf)
<...>
    self.assertTrue(self.res.Succeeded(), msg + output)

AssertionError: False is not true : Command 'expression -- foo()' did not return successfully

Error output:

error: Couldn't look up symbols:

  int foo(void)

Hint: The expression tried to call a function that is not present in the target, perhaps because it was optimized out by the compiler.
```

This patch addresses the issue #129543.
After this patch the size of lldb-server is reduced by 9MB.

Co-authored-by: @bulbazord Alex Langford

This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.

I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.

Add `llvm_unreachable` to prevent warnings/errors in gcc and msvc.

Differential Revision: https://reviews.llvm.org/D119737

Have the different ::Parse.* methods return the demangled string
directly instead of having to go through ::GetBufferRef.

Differential revision: https://reviews.llvm.org/D118953

Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.

After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.