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### Issue Details

* **Electron Version:**
  * <!-- (output of `node_modules/.bin/electron --version`) e.g. 4.0.3 --> 4.1.4
* **Operating System:**
  * <!-- (Platform and Version) e.g. macOS 10.13.6 / Windows 10 (1803) / Ubuntu 18.04 x64 --> Windows 10 (1903)
* **Last Known Working Electron version:**:
  * <!-- (if applicable) e.g. 3.1.0 --> N/A

### Expected Behavior
BrowserWindow.show(), as documented, shows **and** focuses the window.

### Actual Behavior
BrowserWindow.show() doesn't get focus, as noted in https://github.com/TheGoddessInari/rambox/issues/92.
I'm now having to explicitly call .focus() after .show(), even though the documentation explicitly states that .show() also focuses.

### To Reproduce
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### Screenshots
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### Additional Information
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I checked the code, and I don't see NativeWindow call anything like Focus. Maybe I'm looking in the wrong part of the code, but NativeWindowViews::Show() doesn't look to directly or indirectly call NativeWindowViews::Focus(), which is what you would expect from the documentation.

This is possibly specific to Linux? As ShowWindow on Windows **should** activate the window same as Focus does.

Many other applications use .show() and then .focus() on browserwindow, even though the focus is specifically documented as redundant in that case. But either way, the documentation doesn't match the behavior.

It's hard for me to search the code online since GitHub search doesn't seem to support literal searches within "quotes", so I might've missed something.
atom/browser/native_window_views.cc
display::Screen::GetScreen()->GetDisplayNearestPoint(GetPosition());
      SetBounds(display.bounds(), false);
    } else {
      SetBounds(restore_bounds_, false);
    }
    return;
  }
  
  
  widget()->SetFullscreen(fullscreen);
  
  
  
  
  if (leaving_fullscreen && !IsVisible())
    FlipWindowStyle(GetAcceleratedWidget(), true, WS_VISIBLE);
#else
  if (IsVisible())
    widget()->SetFullscreen(fullscreen);
  else if (fullscreen)
    widget()->native_widget_private()->Show(ui::SHOW_STATE_FULLSCREEN,
                                            gfx::Rect());
  
  if (fullscreen)
    SetMenuBarVisibility(false);
  else
    SetMenuBarVisibility(!IsMenuBarAutoHide());
#endif
}
bool NativeWindowViews::IsFullscreen() const {