This is an ongoing series of commits that are reformatting our Python
code. Reformatting is done with `black` (23.1.0).

If you end up having problems merging this commit because you have made
changes to a python file, the best way to handle that is to run `git
checkout --ours <yourfile>` and then reformat it with black.

RFC: https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style

Differential revision: https://reviews.llvm.org/D151460

Eliminate boilerplate of having each test manually assign to `mydir` by calling
`compute_mydir` in lldbtest.py.

Differential Revision: https://reviews.llvm.org/D128077

This just does the usual modernizations such as using new test functions where
possible, clang-formatting the source, avoiding manual process setup,
assert improvements (` assertTrue(a == b) -> assertEqual(a, b)`).

This doesn't add any new test cases but removes some dependence on unrelated
features where possible (e.g., structs declared in functions, using the standard
library to printf stuff or initialize objects).

Follow up to D95813, this converts multiline assertTrue to assertEqual.

Differential Revision: https://reviews.llvm.org/D95899

Convert `assertTrue(a == b)` to `assertEqual(a, b)` to produce better failure messages.

These were mostly done via regex search & replace, with some manual fixes.

Differential Revision: https://reviews.llvm.org/D95813

Displaying large packed bitfields did not work if one was accessing them
through a pointer, and he used the "->" notation ("[0]." notation is
fine). The reason for that is that implicit dereference in -> is plumbed
all the way down to ValueObjectChild::UpdateValue, where the process of
fetching the child value was forked for this flag. The bitfield
"sliding" code was implemented only for the branch which did not require
dereferencing.

This patch restructures the function to avoid this mistake. Processing
now happens in two stages.
- first the parent is dereferenced (if needed)
- then the child value is computed (this step includes sliding and is
  common for both branches)

Differential Revision: https://reviews.llvm.org/D89236

The problem here is in the "sliding" code in
ValueObjectChild::UpdateValue. It modifies m_bitfield_bit_offset and
m_value to ensure the bitfield value fits the window given by the
underlying type.

However, this is broken next time UpdateValue is called, because it
updates the m_value value from the parent. However, the value cannot be
slid again because the m_bitfield_bit_offset is already modified.

It seems this can happen only under specific circumstances. One way to
trigger is is to run an expression which can be interpreted (jitting it
causes a new StackFrame and ValueObject variables to be created).

I fix this bug by modifying m_byte_offset instead of m_scalar, and
ensuring the changes are folded into m_scalar regardless of how many
times UpdateValue is called.

Differential Revision: https://reviews.llvm.org/D88992

Summary: Moves lldbsuite tests to lldb/test/API.

This is a largely mechanical change, moved with the following steps:

```
rm lldb/test/API/testcases
mkdir -p lldb/test/API/{test_runner/test,tools/lldb-{server,vscode}}
mv lldb/packages/Python/lldbsuite/test/test_runner/test lldb/test/API/test_runner
for d in $(find lldb/packages/Python/lldbsuite/test/* -maxdepth 0 -type d | egrep -v "make|plugins|test_runner|tools"); do mv $d lldb/test/API; done
for d in $(find lldb/packages/Python/lldbsuite/test/tools/lldb-vscode -maxdepth 1 -mindepth 1 | grep -v ".py"); do mv $d lldb/test/API/tools/lldb-vscode; done
for d in $(find lldb/packages/Python/lldbsuite/test/tools/lldb-server -maxdepth 1 -mindepth 1 | egrep -v "gdbremote_testcase.py|lldbgdbserverutils.py|socket_packet_pump.py"); do mv $d lldb/test/API/tools/lldb-server; done
```

lldb/packages/Python/lldbsuite/__init__.py and lldb/test/API/lit.cfg.py were also updated with the new directory structure.

Reviewers: labath, JDevlieghere

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71151