[net6] Bump DotNetPreview version to 6.0.100-preview.1.21109.8 (#5610)

* Bump net6 version to 6.0.100-preview.1.21109.8

* Add workaround for linker changes

The linker doesn't load all assemblies anymore. We depend on processing
of all assemblies before `MarkStep`.

Use reflection as temporary workaround to overcome that, until we have
new API in the linker available to handle our processing as part
of `MarkStep`.

* Simplify the workaround

This also gets rid of typo in previous commit, which caused problems
in XF test.

* Not needed anymore

* Simplified it too much

We need at least use the enumerable

* Update reference files

* Add S.D.Common reference

* Add null check with explanatory exception

* Fix whitespace

* Move the package reference

* Add more missing references

* Add more missing references

Author: radekdoulik

Configuration.props

@@ -76,7 +76,7 @@
     <DotNetPreviewTool Condition=" '$(DotNetPreviewTool)' == '' ">$(DotNetPreviewPath)dotnet</DotNetPreviewTool>
     <!-- Version number from: https://github.com/dotnet/installer#installers-and-binaries -->
     <DotNetPreviewVersionBand Condition=" '$(DotNetPreviewVersionBand)' == '' ">6.0.100</DotNetPreviewVersionBand>
-    <DotNetPreviewVersionFull Condition=" '$(DotNetPreviewVersionFull)' == '' ">$(DotNetPreviewVersionBand)-preview.1.21103.13</DotNetPreviewVersionFull>
+    <DotNetPreviewVersionFull Condition=" '$(DotNetPreviewVersionFull)' == '' ">$(DotNetPreviewVersionBand)-preview.1.21109.8</DotNetPreviewVersionFull>
     <ILLinkVersionBand Condition=" '$(ILLinkVersionBand)' == '' ">6.0.0</ILLinkVersionBand>
     <ILLinkVersionFull Condition=" '$(ILLinkVersionFull)' == '' ">$(ILLinkVersionBand)-alpha.1.21109.1</ILLinkVersionFull>
     <WixToolPath Condition=" '$(WixToolPath)' == '' ">$(AndroidToolchainDirectory)\wix\</WixToolPath>

src/Microsoft.Android.Sdk.ILLink/SetupStep.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Reflection;
 using Java.Interop.Tools.Cecil;
+using Mono.Cecil;
 using Mono.Linker;
 using Mono.Linker.Steps;
 using Mono.Tuner;
@@ -25,6 +26,8 @@ List<IStep> Steps {
 			}
 		}
 
+		static MethodInfo getReferencedAssembliesMethod = typeof (LinkContext).GetMethod ("GetReferencedAssemblies", BindingFlags.Public | BindingFlags.Instance);
+
 		protected override void Process ()
 		{
 			string tfmPaths;
@@ -43,9 +46,16 @@ protected override void Process ()
 			subSteps2.Add (new PreserveRegistrations (cache));
 			subSteps2.Add (new PreserveJavaInterfaces ());
 
-			InsertAfter (new FixAbstractMethodsStep (cache), "RemoveUnreachableBlocksStep");
-			InsertAfter (subSteps2, "RemoveUnreachableBlocksStep");
-			InsertAfter (subSteps1, "RemoveUnreachableBlocksStep");
+			InsertAfter (new FixAbstractMethodsStep (cache), "SetupStep");
+			InsertAfter (subSteps2, "SetupStep");
+			InsertAfter (subSteps1, "SetupStep");
+
+			// temporary workaround: this call forces illink to process all the assemblies
+			if (getReferencedAssembliesMethod == null)
+				throw new InvalidOperationException ($"Temporary linker workaround failed, {nameof (getReferencedAssembliesMethod)} is null.");
+
+			foreach (var assembly in (IEnumerable<AssemblyDefinition>)getReferencedAssembliesMethod.Invoke (Context, null))
+				Context.LogMessage ($"Reference assembly to process: {assembly}");
 
 			string proguardPath;
 			if (Context.TryGetCustomData ("ProguardConfiguration", out proguardPath))

src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.ILLink.targets

@@ -56,7 +56,7 @@ This file contains the .NET 5-specific targets to customize ILLink
     <ItemGroup>
       <!-- add our custom steps -->
       <_TrimmerCustomSteps Include="$(MSBuildThisFileDirectory)..\tools\Microsoft.Android.Sdk.ILLink.dll">
-        <BeforeStep>LoadReferencesStep</BeforeStep>
+        <BeforeStep>MarkStep</BeforeStep>
         <Type>Microsoft.Android.Sdk.ILLink.SetupStep</Type>
       </_TrimmerCustomSteps>
     </ItemGroup>

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.ProjectTools/Resources/Base/BuildReleaseArm64SimpleDotNet.apkdesc

@@ -26,25 +26,25 @@
       "Size": 1724
     },
     "classes.dex": {
-      "Size": 316988
+      "Size": 316876
     },
     "assemblies/UnnamedProject.dll": {
       "Size": 2959
     },
     "assemblies/System.Console.dll": {
-      "Size": 6214
+      "Size": 6202
     },
     "assemblies/System.Linq.dll": {
-      "Size": 15127
+      "Size": 15122
     },
     "assemblies/System.Private.CoreLib.dll": {
-      "Size": 516700
+      "Size": 513489
     },
     "assemblies/Java.Interop.dll": {
-      "Size": 63117
+      "Size": 63151
     },
     "assemblies/Mono.Android.dll": {
-      "Size": 86318
+      "Size": 86291
     },
     "lib/arm64-v8a/libxamarin-app.so": {
       "Size": 68560
@@ -59,16 +59,16 @@
       "Size": 100464
     },
     "lib/arm64-v8a/libmonosgen-2.0.so": {
-      "Size": 3831000
+      "Size": 3796008
     },
     "lib/arm64-v8a/libmonodroid.so": {
-      "Size": 250136
+      "Size": 247312
     },
     "lib/arm64-v8a/libxa-internal-api.so": {
       "Size": 65480
     },
     "lib/arm64-v8a/libxamarin-debug-app-helper.so": {
-      "Size": 31672
+      "Size": 37408
     },
     "META-INF/ANDROIDD.SF": {
       "Size": 2512
@@ -80,5 +80,5 @@
       "Size": 2385
     }
   },
-  "PackageSize": 2938815
+  "PackageSize": 2926527
 }

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.ProjectTools/Resources/Base/BuildReleaseArm64SimpleLegacy.apkdesc

@@ -26,22 +26,22 @@
       "Size": 1724
     },
     "classes.dex": {
-      "Size": 316956
+      "Size": 316848
     },
     "assemblies/UnnamedProject.dll": {
-      "Size": 2862
+      "Size": 2863
     },
     "assemblies/Java.Interop.dll": {
-      "Size": 75153
+      "Size": 75279
     },
     "assemblies/Mono.Android.dll": {
-      "Size": 264429
+      "Size": 264424
     },
     "assemblies/mscorlib.dll": {
-      "Size": 769824
+      "Size": 769789
     },
     "assemblies/System.Core.dll": {
-      "Size": 28190
+      "Size": 28191
     },
     "assemblies/System.dll": {
       "Size": 12986
@@ -50,7 +50,7 @@
       "Size": 68560
     },
     "lib/arm64-v8a/libmonodroid.so": {
-      "Size": 250696
+      "Size": 247872
     },
     "lib/arm64-v8a/libxa-internal-api.so": {
       "Size": 65184