[iOS] Remove usage of System.Drawing types

Xamarin.Forms.Platform.iOS/Cells/SwitchCellRenderer.cs

@@ -3,6 +3,7 @@
 using System.Drawing;
 using Foundation;
 using UIKit;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Extensions/LabelExtensions.cs

@@ -3,6 +3,7 @@
 using System.Collections.Generic;
 using System.Drawing;
 using Xamarin.Forms.Internals;
+using SizeF = CoreGraphics.CGSize;
 #if __MOBILE__
 using UIKit;
 using NativeLabel = UIKit.UILabel;

Xamarin.Forms.Platform.iOS/Extensions/UIViewExtensions.cs

@@ -4,6 +4,7 @@
 using System.Linq;
 using static System.String;
 using Xamarin.Forms.Internals;
+using SizeF = CoreGraphics.CGSize;
 #if __MOBILE__
 using UIKit;
 namespace Xamarin.Forms.Platform.iOS

Xamarin.Forms.Platform.iOS/Renderers/ActivityIndicatorRenderer.cs

@@ -2,6 +2,7 @@
 using System.ComponentModel;
 using System.Drawing;
 using UIKit;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/EntryRenderer.cs

@@ -7,6 +7,7 @@
 using UIKit;
 using Xamarin.Forms.PlatformConfiguration.iOSSpecific;
 using Specifics = Xamarin.Forms.PlatformConfiguration.iOSSpecific.Entry;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/FrameRenderer.cs

@@ -2,6 +2,7 @@
 using System.Drawing;
 using CoreGraphics;
 using UIKit;
+using SizeF = CoreGraphics.CGSize;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/SearchBarRenderer.cs

@@ -5,6 +5,7 @@
 using Foundation;
 using UIKit;
 using Xamarin.Forms.PlatformConfiguration.iOSSpecific;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/SliderRenderer.cs

@@ -198,7 +198,7 @@ void UpdateTapRecognizer()
 							if (control != null)
 							{
 								var tappedLocation = recognizer.LocationInView(control);
-								if (tappedLocation != null)
+								if (tappedLocation != default)
 								{
 									var val = (tappedLocation.X - control.Frame.X) * control.MaxValue / control.Frame.Size.Width;
 									Element.SetValueFromRenderer(Slider.ValueProperty, val);

Xamarin.Forms.Platform.iOS/Renderers/StepperRenderer.cs

@@ -2,6 +2,7 @@
 using System.Drawing;
 using System.ComponentModel;
 using UIKit;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/SwitchRenderer.cs

@@ -2,6 +2,7 @@
 using System.ComponentModel;
 using System.Drawing;
 using UIKit;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/Renderers/TabbedRenderer.cs

@@ -9,6 +9,7 @@
 using PageUIStatusBarAnimation = Xamarin.Forms.PlatformConfiguration.iOSSpecific.UIStatusBarAnimation;
 using TabbedPageConfiguration = Xamarin.Forms.PlatformConfiguration.iOSSpecific.TabbedPage;
 using TranslucencyMode = Xamarin.Forms.PlatformConfiguration.iOSSpecific.TranslucencyMode;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {
@@ -133,7 +134,7 @@ public override void ViewDidLayoutSubviews()
 
 			if (!Element.Bounds.IsEmpty)
 			{
-				View.Frame = new System.Drawing.RectangleF((float)Element.X, (float)Element.Y, (float)Element.Width, (float)Element.Height);
+				View.Frame = new RectangleF((float)Element.X, (float)Element.Y, (float)Element.Width, (float)Element.Height);
 			}
 
 			var frame = View.Frame;

Xamarin.Forms.Platform.iOS/Renderers/WkWebViewRenderer.cs

@@ -16,6 +16,7 @@
 using Xamarin.Forms.Internals;
 using PreserveAttribute = Foundation.PreserveAttribute;
 using Uri = System.Uri;
+using RectangleF = CoreGraphics.CGRect;
 
 namespace Xamarin.Forms.Platform.iOS
 {

Xamarin.Forms.Platform.iOS/VisualElementTracker.cs

@@ -5,6 +5,8 @@
 using CoreAnimation;
 using CoreGraphics;
 using Xamarin.Forms.Internals;
+using RectangleF = CoreGraphics.CGRect;
+using PointF = CoreGraphics.CGPoint;
 
 #if __MOBILE__
 using UIKit;