[clang-format] Continue aligned lines better (#161903)

Fixes #53497.

Fixes #56078.

after with config `{AlignConsecutiveAssignments: true}`

```C++
auto aaaaaaaaaaaaaaaaaaaaa = {};
auto b                     = [] {
  x = {.one_foooooooooooooooo = 2, //
       .two_fooooooooooooo    = 3, //
       .three_fooooooooooooo  = 4};
};

A B          = {"Hello "
                "World"};
BYTE payload = 2;

float i2 = 0;
auto v   = type{i2 = 1, //
                i  = 3};
```

before

```C++
auto aaaaaaaaaaaaaaaaaaaaa = {};
auto b                     = [] {
  x = {.one_foooooooooooooooo = 2, //
                           .two_fooooooooooooo    = 3, //
                           .three_fooooooooooooo  = 4};
};

A B          = {"Hello "
                         "World"};
BYTE payload = 2;

float i2 = 0;
auto v   = type{i2 = 1, //
              i  = 3};
```

When a line gets aligned, the following lines may need to move with it.
This patch replaces the old algorithm with a simpler one.  It uses the
`IsAligned` attribute.  It makes most of the scope stack irrelevant.
Now the stack only needs to keep track of 2 levels.

The old algorithm had problems like these.

- Whether lines inside a braced list moved depended on whether there was
  a type at the start.  It should depend on whether the inside was
  aligned to the brace.  The first case that came up with a type name at
  the start happened to have a comma at the end of the list so the
  inside was not aligned to the brace.

- Excluding lines inside closures did not always work.

- A continued string could move twice as much as it should.

The following problems are not fixed yet.

A token that opens a scope is needed.  Operator precedence is not
enough.

```C++
auto aaaaaaaaaaaaaaaaaaaaa = {};
auto b                     = 0 + //
         0;
```

The algorithm has trouble when things that should not move and things
that should move are nested.  This is related to the `IsAligned`
attribute being a boolean.  It also affects how spaces and tabs are
selected.

```C++
auto aaaaaaaaaaaaaaaaaaaaa = {};
auto b                     = {.a = {
              .a = 0,
          }};
```

0 files changed, 0 insertions, 0 deletions