[iOS] SearchBar width is not currently consistent with other platforms or across ios versions

Case 1

<Grid>
			<Grid.RowDefinitions>
				<RowDefinition></RowDefinition>
				<RowDefinition></RowDefinition>
				<RowDefinition></RowDefinition>
			</Grid.RowDefinitions>
			<StackLayout Orientation="Horizontal" BackgroundColor="Yellow">
				<SearchBar Text="CenterSearchBar" HorizontalOptions="Center"></SearchBar>
			</StackLayout>
			<StackLayout Grid.Row="1"  Orientation="Horizontal" BackgroundColor="Yellow">
				<Entry Text="CenterEntry" HorizontalOptions="Center" BackgroundColor="Green"></Entry>
			</StackLayout>
			<StackLayout Grid.Row="2"  Orientation="Horizontal" BackgroundColor="Yellow">
				<Label Text="CenterLabel" HorizontalOptions="Center" BackgroundColor="Green"></Label>
			</StackLayout>
		</Grid>

Android

iOS 11

Case 2

<StackLayout Orientation="Vertical" BackgroundColor="Pink">
				<StackLayout Orientation="Horizontal" BackgroundColor="Yellow">
					<SearchBar Text="Center" HorizontalOptions="Center"></SearchBar>
				</StackLayout>
				<StackLayout Orientation="Horizontal">
					<SearchBar Text="CenterAndExpand" HorizontalOptions="CenterAndExpand"></SearchBar>
				</StackLayout>
				<StackLayout Orientation="Horizontal">
					<SearchBar Text="Nothing"></SearchBar>
				</StackLayout>
				<StackLayout Orientation="Horizontal">
					<Label Text="hello stuffed marshmellow"></Label>
					<Label Text="hello stuffed marshmellow"></Label>
					<Label Text="hello stuffed marshmellow"></Label>
					<SearchBar></SearchBar>
					<Label Text="hello stuffed marshmellow"></Label>
					<Label Text="hello stuffed marshmellow"></Label>
					<Label Text="hello stuffed marshmellow"></Label>
				</StackLayout>
			</StackLayout>

Android

ios11

ios10

Steps to Reproduce

Run attached Repro

it has two pages that have the XAML above

Expected Behavior

All platforms (ios versions) should look the same

Actual Behavior

All platforms (ios versions) do not look the same

Basic Information

• Version with issue: 3.2 pre3
• Last known good version:
• IDE:
• Platform Target Frameworks:
  • iOS: 11.4 and 10.3
  • Android: 8.0

Reproduction Link

Dogfood32.zip