[cpp] insufficient indentation when declaring lambda with name and { on separate lines

[takamori]

Pressing enter after the { results in indentation of 2 spaces rather than 6.

auto long_function_name_requires_new_line_______________________________ =
    []() {
      int x = 1;
      int y = 2;
    };

[marijnh]

If you have a function definition like below, I suppose 2-space indent is the expected indentation, right?

void foo(
    int a,
    int b) {
  return
}

The indentation logic intentionally indents braced bodies two spaces beyond the statement that started them, regardless of the indentation of the line that started them. I could remove that, but I think it'll cause unexpected behavior in other situations.