Disable hotkeys on static QFileDialog calls

[malleoz]

Previously, if you had "Hotkeys Require Window Focus" disabled, you could repeatedly use the "Open" hotkey, for example, to stack File Open windows over top of each other over and over.

This PR just adds a wrapper function to toggle hotkeys for QFileDialogs. Thank you to lioncache for the approach.

[lioncash]

I think you may want to create wrapper functions for using the QFileDialog functions, e.g.

// Feel free to put all of this behind a descriptive namespace.

class HotkeyDisabler final
{
public:
  HotkeyDisabler() { HotkeyManagerEmu::Enable(false); }
  ~HotkeyDisabler() { HotkeyManagerEmu::Enable(true); }
};

QString GetExistingDirectory(QWidget *parent = nullptr, const QString& caption = {},
                             const QString& dir = {}, QFileDialog::Options options = QFileDialog::ShowDirsOnly)
{
  const HotkeyDisabler disabler;
  return QFileDialog::getExistingDirectory(parent, caption, dir, options);
}

// ... etc for other relevant functions.

and then using those wrappers over the direct QFileDialog ones.

Pasting the enable and disable calls around every single call individually is both super fragile and error-prone (and not to mention pretty ugly), so reducing the need to do that as much as possible would be nice.

[malleoz]

This is the approach I was hoping for, I wasn't able to conceptualize how to do it. I'll mark this as a draft while I take time to implement your suggestion between travelling this weekend. Thanks!

[malleoz]

Hopefully this was done in a proper way. Works on my end perfectly!

[leoetlino]

Seems sane, though I cannot reproduce the Open hotkey issue on Linux.

Reviewed 16 of 16 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @malleoz)