Add activity-alias support (#9654)

Context: https://dev.azure.com/devdiv/DevDiv/_workitems/edit/2305723
Context: https://github.com/mattleibow/MauiAppWithMultipleIcons

Apparently launching an activity-alias was not supported at all. That
probably means very few people use it, however we really should be
able to launch them.

The changes to `android-platform-support` include the ability for
`GetAndroidActivityName` to find `activity-alias` elements which have
the correct metadata. This allows us to launch them via the typical
`Run` command to launch them. 

Added a unit test.

Bump to DevDiv/android-platform-support/main@cc26de2b

* Merged PR 595972: Add support for activity-alias...

.external

@@ -1 +1 @@
-DevDiv/android-platform-support:main@3b4e16f197ff3e102ffb59af0b0f056046cc7658
+DevDiv/android-platform-support:main@cc26de2b33292462ab2daa70c593c78ef2a241e7

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.ProjectTools/Resources/Base/MainActivity.cs

@@ -11,6 +11,7 @@
 namespace ${ROOT_NAMESPACE}
 {
 	[Register ("${JAVA_PACKAGENAME}.MainActivity"), Activity (Label = "${PROJECT_NAME}", MainLauncher = true, Icon = "@drawable/icon")]
+	//${ATTRIBUTES}
 	public class MainActivity : Activity
 	{
 		//${FIELDS}

tests/MSBuildDeviceIntegration/Tests/InstallAndRunTests.cs

@@ -46,6 +46,33 @@ public void DotNetRun ([Values (true, false)] bool isRelease)
 			Assert.IsTrue (didLaunch, "Activity should have started.");
 		}
 
+		[Test]
+		public void ActivityAliasRuns ([Values (true, false)] bool isRelease)
+		{
+			var proj = new XamarinAndroidApplicationProject {
+				IsRelease = isRelease
+			};
+			proj.AndroidManifest = proj.AndroidManifest.Replace ("</application>", @"
+<activity-alias
+			android:name="".MainActivityAlias""
+			android:enabled=""true""
+			android:icon=""@drawable/icon""
+			android:targetActivity="".MainActivity""
+			android:exported=""true"">
+			<intent-filter>
+				<action android:name=""android.intent.action.MAIN"" />
+				<category android:name=""android.intent.category.LAUNCHER"" />
+			</intent-filter>
+		</activity-alias>
+</application>");
+			proj.MainActivity = proj.DefaultMainActivity.Replace ("//${ATTRIBUTES}",$"[Register(\"{proj.PackageName}.MainActivity\")]").Replace("MainLauncher = true", "MainLauncher = false");
+			using var builder = CreateApkBuilder ();
+			Assert.IsTrue (builder.Install (proj), "Install should have succeeded.");
+			RunProjectAndAssert (proj, builder);
+			Assert.True (WaitForActivityToStart (proj.PackageName, "MainActivityAlias",
+				Path.Combine (Root, builder.ProjectDirectory, "logcat.log"), 30), "Activity MainActivityAlias should have started.");
+		}
+
 		[Test]
 		public void NativeAssemblyCacheWithSatelliteAssemblies ([Values (true, false)] bool enableMarshalMethods)
 		{