Reconcile Essentials API's with MAUI

[Redth]

Historically Xamarin.Essentials and Forms had similar API's doing the same things, but because they were never in the same package, they were both necessary.

We need to reconcile this and move API's or change their implementation to use a common base. After an initial call we identified these API's which need attention:

Device

• Remove Device.Flags/SetFlags() #4478 and Remove Device.OpenUri implementation and Device.Flags/SetFlags #2651
• Device.FlowDirection - Windows FlowDirection #4936
• Idiom Make Device.Idiom and Device.RuntimePlatform use Essentials #4548
• RuntimePlatform Make Device.Idiom and Device.RuntimePlatform use Essentials #4548
• Remove IPlatformInvalidate and Device.Invalidate() #4479
• Info - obsolete (hidden) Remove Forms DeviceInfo and use Essentials #3213

Move these to Window, use Application.Windows.First() to back these and obsolete them:

• IsInvokeRequired Move IDispatcher logic out of IPlatformServices #2862
• BeginInvokeOnMainThread(Action) Move IDispatcher logic out of IPlatformServices #2862
• GetMainThreadSynchronizationContextAsync Move IDispatcher logic out of IPlatformServices #2862
• InvokeOnMainThreadAsync(Func) Move IDispatcher logic out of IPlatformServices #2862
• InvokeOnMainThreadAsync(Action) Move IDispatcher logic out of IPlatformServices #2862
• InvokeOnMainThreadAsync(Func<Task>) Move IDispatcher logic out of IPlatformServices #2862
• InvokeOnMainThreadAsync(Func) Move IDispatcher logic out of IPlatformServices #2862

PlatformServices

• RequestedTheme - Remove IPlatformServices.RequestedTheme and use Essentials #4964
• GetHash - remove Remove IPlatformServices.GetHash #2707
• GetMD5Hash - remove Remove IPlatformServices.GetHash #2707
• Remove Device.GetNamedColor #4492
• Moved IPlatformServices.GetNamedSize into a separate service #4570
• GetPlatformSize - Moved GetPlatformSize logic into a new service #4885
• GetStreamAsync - remove Remove usage of IsolatedStorage #2710
• GetUserStoreForApplication - remove Remove usage of IsolatedStorage #2710
• OpenUriAction - obsolete, use essentials Remove Device.OpenUri implementation and Device.Flags/SetFlags #2651
• QuitApplication - move to application Add ApplicationHandler #2653
• StartTimer - Add more APIs to IDispatcher #4944

Application

• Dispatcher - find window of mainpage and use that dispatcher Move IDispatcher logic out of IPlatformServices #2862
• MainPage / CreateWindow
  Make CreateWindow return MainPage, if no mainpage is set throw
  Set MainPage, go through windows to find window with current mainpage, and replace mainpage
• GetMainThreadSynchronizationContextAsync Move IDispatcher logic out of IPlatformServices #2862

[mattleibow]

Finally ready to close!!! Was nice knowing you IPlatformServices!