Arrays, call chains, ident_style and hard_tabs

The method chain, starting with .iter() should be indented, but it's not.

fn foo(&self) {
    let coords: Vec<_> = [
        (self.y - 1, self.x),
        (self.y, self.x - 1),
        (self.y, self.x + 1),
        (self.y + 1, self.x),
    ]
    .iter()
    .filter_map(...)
    .filter(...)
    .map(...)
    .collect();
}

This can be somewhat mitigated by setting indent_style = "Visual", but:
a) I don't like that style very much, because the call chain becomes too indented (it looks worse when there are actual lambdas instead of ...)

fn foo(&self) {
    let coords: Vec<_> =
        [(self.y - 1, self.x),
         (self.y, self.x - 1),
         (self.y, self.x + 1),
         (self.y + 1, self.x)].iter()
                              .filter_map(...)
                              .filter(...)
                              .map(...)
                              .collect();
}

b) It conflicts with hard_tabs = true:

fn foo(&self) {
    let coords: Vec<_> = [
                          (self.y - 1, self.x),
                          (self.y, self.x - 1),
                          (self.y, self.x + 1),
                          (self.y + 1, self.x),
    ].iter()
                         .filter_map(...)
                         .filter(...)
                         .map(...)
                         .collect();
}

Combination of hard_tabs = true and indent_style = "Visual" chose to align some parts of the call chain (except the first one) with elements of the vector. As result, .iter() looks very disconnected from the rest.

This is similar to #3157 but has different trigger.

$ rustfmt --version
rustfmt 1.0.1-nightly (be13559 2018-12-10)

Start by reproducing the example with rustfmt, then compare the output under the default and Visual indent_style settings with hard_tabs enabled. Trace the formatter's handling of array expressions followed by call chains; done means the reported chain indentation is corrected without the described Visual and hard-tabs regressions.