Merges unpkg-submodule branch into main, make the repo submodule ready (

#1325)

Takes changes made by Scott  Jones (@Scottj1s) to make WinUIgallery act as a submodule. It also gets rid of WAP project for a single project solution. More work needed in that area for supporting unpackaged apps.

Directory.Build.props

@@ -0,0 +1,3 @@
+<Project>
+  <Import Project="$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))" Condition="Exists($([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../')))" />
+</Project>

WinUIGallery/Directory.Build.props

@@ -7,11 +7,8 @@
 
   <Import Project="$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))" Condition="Exists($([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../')))" />
 
-  <!-- When building standalone, WinUI Gallery needs to do some extra things that are done implicitly in the WinUI repo.
-       Determine if building standalone by conditioning on the MuxCustomBuildTasksPackageVersion property, which only exists in the WinUI repo -->
-  <PropertyGroup Condition="'$(MuxCustomBuildTasksPackageVersion)' != ''">
-    <IsInWinUIRepo>true</IsInWinUIRepo>
-
+  <!-- When building standalone, WinUI Gallery needs to do some extra things that are done implicitly in the WinUI repo.-->
+  <PropertyGroup Condition="'$(IsInWinUIRepo)' == 'true'">
     <!-- We want to binplace the WinUI Gallery pdb to a subdirectory of Symbols\Test so that the UWP and Desktop versions don't 
          overwrite each other. -->
     <BinplaceSymbolsToSubdir>true</BinplaceSymbolsToSubdir>

WinUIGallery/Package.MSIX.appxmanifest

@@ -0,0 +1,51 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Package 
+  xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10" 
+  xmlns:mp="http://schemas.microsoft.com/appx/2014/phone/manifest" 
+  xmlns:uap="http://schemas.microsoft.com/appx/manifest/uap/windows10" 
+  xmlns:uap3="http://schemas.microsoft.com/appx/manifest/uap/windows10/3" 
+  xmlns:rescap="http://schemas.microsoft.com/appx/manifest/foundation/windows10/restrictedcapabilities"
+  IgnorableNamespaces="uap mp uap3">
+  <Identity Name="Microsoft.WinUI3ControlsGallery.Desktop" Publisher="CN=WinUITest" Version="1.3.6.0" />
+  <mp:PhoneIdentity PhoneProductId="863667e0-667a-4bb4-ac52-c59656c7333a" PhonePublisherId="00000000-0000-0000-0000-000000000000" />
+  <Properties>
+    <DisplayName>WinUI 3 Gallery</DisplayName>
+    <PublisherDisplayName>Microsoft Corporation</PublisherDisplayName>
+    <Logo>Assets\Tiles\StoreLogo-sdk.png</Logo>
+    <uap:SupportedUsers>multiple</uap:SupportedUsers>
+  </Properties>
+  <Resources>
+    <Resource Language="x-generate" />
+  </Resources>
+  <Applications>
+    <Application Id="App" Executable="$targetnametoken$.exe" EntryPoint="$targetentrypoint$">
+      <uap:VisualElements DisplayName="WinUI 3 Gallery" Square150x150Logo="Assets\Tiles\squaretile-sdk.png" Square44x44Logo="Assets\Tiles\SmallTile-sdk.png" Description="WinUI 3 Gallery" BackgroundColor="transparent">
+        <uap:DefaultTile Square310x310Logo="Assets\Tiles\LargeTile.png" Wide310x150Logo="Assets\Tiles\WideTile.png" Square71x71Logo="Assets\Tiles\SmallTile.png">
+          <uap:ShowNameOnTiles>
+            <uap:ShowOn Tile="square150x150Logo" />
+            <uap:ShowOn Tile="wide310x150Logo" />
+            <uap:ShowOn Tile="square310x310Logo" />
+          </uap:ShowNameOnTiles>
+        </uap:DefaultTile>
+        <uap:SplashScreen Image="Assets\Tiles\splash-sdk.png" BackgroundColor="#00b2f0" />
+      </uap:VisualElements>
+      <Extensions>
+        <uap3:Extension Category="windows.appUriHandler">
+          <uap3:AppUriHandler>
+            <uap3:Host Name="winuigallery.com" />
+            <uap3:Host Name="xamlcontrolsgallery.com" />
+          </uap3:AppUriHandler>
+        </uap3:Extension>
+        <uap:Extension Category="windows.protocol">
+          <uap:Protocol Name="winui3gallery">
+            <uap:DisplayName>WinUI 3 Gallery</uap:DisplayName>
+          </uap:Protocol>
+        </uap:Extension>
+      </Extensions>
+    </Application>
+  </Applications>
+  <Capabilities>
+    <rescap:Capability Name="runFullTrust" />
+    <Capability Name="internetClient" />
+  </Capabilities>
+</Package>