Fix consumption of fluentui-ios (built with Xcode 11) when building w…

…ith Xcode 12 (microsoft#231)

* Minor fixes

* Fix swift-lint

* Use spaces instead of tabs

* More tabs to spaces

* Update comment

ios/FluentUI/Navigation/NavigationBar.swift

@@ -40,12 +40,18 @@ open class NavigationBarTopAccessoryViewAttributes: NSObject {
         self.minWidth = minWidth
         super.init()
     }
+
+    public override init() {
+        self.widthMultiplier = 1.0
+        self.maxWidth = .greatestFiniteMagnitude
+        self.minWidth = .zero
+    }
 }
 
 /// Layout attributes for a navigation bar's top search bar.
 @objc(MSFNavigationBarTopSearchBarAttributes)
 open class NavigationBarTopSearchBarAttributes: NavigationBarTopAccessoryViewAttributes {
-    @objc public init() {
+    @objc public override init() {
         super.init(widthMultiplier: Constants.widthMultiplier, maxWidth: Constants.viewMaxWidth, minWidth: Constants.viewMinWidth)
     }
 

ios/FluentUI/Popup Menu/PopupMenuController.swift

@@ -309,7 +309,7 @@ extension PopupMenuController: UITableViewDataSource {
         let identifier = String(describing: cellClass)
         tableView.register(cellClass, forCellReuseIdentifier: identifier)
 
-        let cell = tableView.dequeueReusableCell(withIdentifier: identifier) as! PopupMenuItemTemplateCell
+        let cell = tableView.dequeueReusableCell(withIdentifier: identifier) as! (PopupMenuItemTemplateCell & TableViewCell)
         cell.setup(item: item)
         cell.preservesSpaceForImage = itemsHaveImages
 

ios/FluentUI/Popup Menu/PopupMenuProtocols.swift

@@ -35,10 +35,10 @@ public protocol PopupMenuTemplateItem: AnyObject {
 /**
 `PopupMenuItemTemplateCell` represents a template cell protocol inside `PopupMenuController`.
  The built-in type is `PopupMenuItemCell`.
- You can use `UITableViewCell` conforms to this protocol for customization.
+ If you are making a custom object conform to this protocol, it must be a `UITableViewCell` for the Pop Up Menu to work properly
 */
 @objc(MSFPopupMenuItemTemplateCell)
-public protocol PopupMenuItemTemplateCell where Self: UITableViewCell {
+public protocol PopupMenuItemTemplateCell {
     /// `PopupMenuController` will notify that one or more items in the list contain image(s)
     @objc var preservesSpaceForImage: Bool { get set }
     /// `PopupMenuController` will notify the custom separatorColor.