[Enhancement] Add SearchBar platform specific for IsSpellCheckEnabled

[rmarinho]

Rationale

There's no way to set IsSpellCheckEnabled on the AutoSugestBox, so we need to change the control template, and also expose a new platform specific to change this property inside the control template

Implementation

We need to create a control template

Allow to enable SpellCheck for SearchBar

SearchBar.On<UWP>().IsSpellCheckEnabled();
SearchBar.On<UWP>().SetSpellCheckEnabled(true/false);
SearchBar.On<UWP>().EnableSpellCheck();
SearchBar.On<UWP>().DisableSpellCheck();

public static readonly BindableProperty IsSpellCheckEnabled Property = BindableProperty.Create("IsSpellCheckEnabled ", typeof(bool), typeof(SearchBar), false);

Expected Result

Android

None

iOS

None

UWP

Alter the default control template for AutoSuggestBox and set the property IsSpellCheckEnabled on TextBox

Implications for CSS

None

Backward Compatibility

Third party renderers may need to be updated to ensure that this functionality is supported through the new official mechanism. Further we will need to be careful to code the changes to the renderers in a careful manner to ensure that if someone is already using an effect support this feature that the effect is as best as possible not broken by our changes.

Difficulty : Easy