[Xamarin.Android.Build.Tasks] Don't deploy Facade assemblies (#337)

A change "somewhere" has recently causes this issue. The problem is
in Release mode we now include the Facade assemblies in the package.
Which is something we definately should NOT be doing.

That said we do need the Facades in order for Linking and Aot to
work since Cecil needs to be able to load them.
So what this commit does is make sure the `ResolveAssemblies` task
adds metadata for the Facades. We can then use that in the `BuildApk`
Task to filter out the assemblies we do not want to ship.

src/Xamarin.Android.Build.Tasks/Tasks/ResolveAssemblies.cs

@@ -23,6 +23,8 @@ public class ResolveAssemblies : Task
 		[Required]
 		public string ReferenceAssembliesDirectory { get; set; }
 
+		public ITaskItem[] DesignTimeFacadeDirectories { get; set; }
+
 		public string I18nAssemblies { get; set; }
 		public string LinkMode { get; set; }
 
@@ -56,11 +58,12 @@ bool Execute (DirectoryAssemblyResolver resolver)
 			Log.LogDebugMessage ("  I18nAssemblies: {0}", I18nAssemblies);
 			Log.LogDebugMessage ("  LinkMode: {0}", LinkMode);
 			Log.LogDebugTaskItems ("  Assemblies:", Assemblies);
+			Log.LogDebugTaskItems ("  DesignTimeFacadeDirectories:", DesignTimeFacadeDirectories);
 
 			foreach (var dir in ReferenceAssembliesDirectory.Split (new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries))
 				resolver.SearchDirectories.Add (dir);
 
-			var assemblies = new HashSet<string> ();
+			var assemblies = new HashSet<ITaskItem> (new ITaskItemEqualityComparer ());
 
 			var topAssemblyReferences = new List<AssemblyDefinition> ();
 
@@ -76,7 +79,7 @@ bool Execute (DirectoryAssemblyResolver resolver)
 					if (assemblyDef == null)
 						throw new InvalidOperationException ("Failed to load assembly " + assembly.ItemSpec);
 					topAssemblyReferences.Add (assemblyDef);
-					assemblies.Add (Path.GetFullPath (assemblyDef.MainModule.FullyQualifiedName));
+					assemblies.Add (new TaskItem (Path.GetFullPath (assemblyDef.MainModule.FullyQualifiedName)));
 				}
 			} catch (Exception ex) {
 				Log.LogError ("Exception while loading assemblies: {0}", ex);
@@ -93,8 +96,8 @@ bool Execute (DirectoryAssemblyResolver resolver)
 			// Add I18N assemblies if needed
 			AddI18nAssemblies (resolver, assemblies);
 
-			ResolvedAssemblies = assemblies.Select (a => new TaskItem (a)).ToArray ();
-			ResolvedSymbols = assemblies.Select (a => a + ".mdb").Where (a => File.Exists (a)).Select (a => new TaskItem (a)).ToArray ();
+			ResolvedAssemblies = assemblies.ToArray ();
+			ResolvedSymbols = assemblies.Select (a => new TaskItem (a + ".mdb")).Where (a => File.Exists (a.ItemSpec)).ToArray ();
 			ResolvedFrameworkAssemblies = ResolvedAssemblies.Where (p => MonoAndroidHelper.IsFrameworkAssembly (p.ItemSpec, true)).ToArray ();
 			ResolvedUserAssemblies = ResolvedAssemblies.Where (p => !MonoAndroidHelper.IsFrameworkAssembly (p.ItemSpec, true)).ToArray ();
 			ResolvedDoNotPackageAttributes = do_not_package_atts.ToArray ();
@@ -110,13 +113,14 @@ bool Execute (DirectoryAssemblyResolver resolver)
 		readonly List<string> do_not_package_atts = new List<string> ();
 		int indent = 2;
 
-		void AddAssemblyReferences (DirectoryAssemblyResolver resolver, ICollection<string> assemblies, AssemblyDefinition assembly, bool topLevel)
+		void AddAssemblyReferences (DirectoryAssemblyResolver resolver, ICollection<ITaskItem> assemblies, AssemblyDefinition assembly, bool topLevel)
 		{
 			var fqname = assembly.MainModule.FullyQualifiedName;
 			var fullPath = Path.GetFullPath (fqname);
+			var item = new TaskItem (fullPath);
 
 			// Don't repeat assemblies we've already done
-			if (!topLevel && assemblies.Contains (fullPath))
+			if (!topLevel && assemblies.Contains (item))
 				return;
 
 			foreach (var att in assembly.CustomAttributes.Where (a => a.AttributeType.FullName == "Java.Interop.DoNotPackageAttribute")) {
@@ -129,8 +133,11 @@ void AddAssemblyReferences (DirectoryAssemblyResolver resolver, ICollection<stri
 			Log.LogMessage (MessageImportance.Low, "{0}Adding assembly reference for {1}, recursively...", new string (' ', indent), assembly.Name);
 			indent += 2;
 			// Add this assembly
-			if (!topLevel && assemblies.All (a => new AssemblyNameDefinition (a, null).Name != assembly.Name.Name))
-				assemblies.Add (fullPath);
+			if (!topLevel && assemblies.All (a => new AssemblyNameDefinition (a.ItemSpec, null).Name != assembly.Name.Name)) {
+				var path = Path.GetDirectoryName (fullPath);
+				item.SetMetadata ("ResolvedFrom", DesignTimeFacadeDirectories.Any (x =>  Path.GetDirectoryName (x.ItemSpec).StartsWith (Path.GetDirectoryName (path))) ? "ImplicitlyExpandDesignTimeFacades" : "");
+				assemblies.Add (item);
+			}
 
 			// Recurse into each referenced assembly
 			foreach (AssemblyNameReference reference in assembly.MainModule.AssemblyReferences) {
@@ -152,7 +159,7 @@ static LinkModes ParseLinkMode (string linkmode)
 			return mode;
 		}
 
-		void AddI18nAssemblies (DirectoryAssemblyResolver resolver, ICollection<string> assemblies)
+		void AddI18nAssemblies (DirectoryAssemblyResolver resolver, ICollection<ITaskItem> assemblies)
 		{
 			var i18n = Linker.ParseI18nAssemblies (I18nAssemblies);
 			var link = ParseLinkMode (LinkMode);
@@ -179,10 +186,10 @@ void AddI18nAssemblies (DirectoryAssemblyResolver resolver, ICollection<string>
 				assemblies.Add (ResolveI18nAssembly (resolver, "I18N.West"));
 		}
 
-		string ResolveI18nAssembly (DirectoryAssemblyResolver resolver, string name)
+		ITaskItem ResolveI18nAssembly (DirectoryAssemblyResolver resolver, string name)
 		{
 			var assembly = resolver.Resolve (AssemblyNameReference.Parse (name));
-			return Path.GetFullPath (assembly.MainModule.FullyQualifiedName);
+			return new TaskItem (Path.GetFullPath (assembly.MainModule.FullyQualifiedName));
 		}
 	}
 }

src/Xamarin.Android.Build.Tasks/Utilities/ITaskItemEqualityComparer.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.Build.Framework;
+
+namespace Xamarin.Android.Tasks
+{
+	public class ITaskItemEqualityComparer : IEqualityComparer<ITaskItem>
+	{
+		public bool Equals (ITaskItem x, ITaskItem y)
+		{
+			if (x == null || y == null)
+				return false;
+			return x.ItemSpec == y.ItemSpec;
+		}
+
+		public int GetHashCode (ITaskItem obj)
+		{
+			if (obj == null)
+				return 0;
+			return obj.ItemSpec.GetHashCode ();
+		}
+	}
+}

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj

@@ -393,6 +393,9 @@
     <Compile Include="Utilities\Files.cs">
       <Link>Utilities\Files.cs</Link>
     </Compile>
+    <Compile Include="Utilities\ITaskItemEqualityComparer.cs">
+      <Link>Utilities\ITaskItemEqualityComparer.cs</Link>
+    </Compile>
     <Compile Include="$(LinkerSourceFullPath)\tuner\Mono.Tuner\ApplyPreserveAttributeBase.cs">
       <Link>Linker\Mono.Tuner\ApplyPreserveAttributeBase.cs</Link>
     </Compile>

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Common.targets

@@ -1236,6 +1236,7 @@ because xbuild doesn't support framework reference assemblies.
 		_GetAdditionalResourcesFromAssemblies;
 		_CreateAdditionalResourceCache;
 		_GenerateAndroidResourceDir;
+		_ValidateAndroidPackageProperties;
 	</_UpdateAndroidResgenDependsOnTargets>
 </PropertyGroup>
 
@@ -1409,6 +1410,7 @@ because xbuild doesn't support framework reference assemblies.
 		Assemblies="$(OutDir)$(TargetFileName);@(FilteredAssemblies)"
 		I18nAssemblies="$(MandroidI18n)"
 		LinkMode="$(AndroidLinkMode)"
+		DesignTimeFacadeDirectories="@(DesignTimeFacadeDirectories)"
 		ReferenceAssembliesDirectory="$(TargetFrameworkDirectory)">
       <Output TaskParameter="ResolvedAssemblies" ItemName="ResolvedAssemblies" />
       <Output TaskParameter="ResolvedUserAssemblies" ItemName="ResolvedUserAssemblies" />
@@ -1614,6 +1616,7 @@ because xbuild doesn't support framework reference assemblies.
 <Target Name="_PrepareAssemblies" DependsOnTargets="$(_PrepareAssembliesDependsOnTargets)">
   <!-- Update our assembly lists to the copies for linking.  We also need to verify
        they still exist cause linking will delete them if they aren't used -->
+
   <GetFilesThatExist
     Condition="'$(AndroidLinkMode)' != 'None'"
     Files="@(ResolvedAssemblies->'$(MonoAndroidIntermediateAssetsDir)%(Filename)%(Extension)')">
@@ -1640,36 +1643,42 @@ because xbuild doesn't support framework reference assemblies.
 
   <CreateItem
     Include="@(ResolvedAssemblies->'$(MonoAndroidIntermediateAssemblyDir)%(Filename)%(Extension)')"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' == 'None'">
     <Output TaskParameter="Include" ItemName="_ResolvedAssemblies" />
   </CreateItem>
 
   <CreateItem
     Include="@(ResolvedSymbols->'$(MonoAndroidIntermediateAssemblyDir)%(Filename)%(Extension)')"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' == 'None'">
     <Output TaskParameter="Include" ItemName="_ResolvedSymbols" />
   </CreateItem>
 
   <CreateItem
     Include="@(ResolvedUserAssemblies->'$(MonoAndroidIntermediateAssemblyDir)%(Filename)%(Extension)')"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' == 'None'">
     <Output TaskParameter="Include" ItemName="_ResolvedUserAssemblies" />
   </CreateItem>
 
   <CreateItem
     Include="@(ResolvedFrameworkAssemblies)"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' == 'None'">
     <Output TaskParameter="Include" ItemName="_ResolvedFrameworkAssemblies" />
   </CreateItem>
 
   <CreateItem
     Include="@(_ResolvedFrameworkAssemblies)"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' == 'None' OR '$(AndroidUseSharedRuntime)' == 'true'">
     <Output TaskParameter="Include" ItemName="_ShrunkFrameworkAssemblies" />
   </CreateItem>
 
   <CreateItem
     Include="@(_ResolvedFrameworkAssemblies->'$(MonoAndroidIntermediateAssetsDir)shrunk\%(Filename)%(Extension)')"
+    PreserveExistingMetadata="True"
     Condition="'$(AndroidLinkMode)' != 'None' AND '$(AndroidUseSharedRuntime)' != 'true'">
     <Output TaskParameter="Include" ItemName="_ShrunkFrameworkAssemblies" />
   </CreateItem>
@@ -1735,6 +1744,7 @@ because xbuild doesn't support framework reference assemblies.
 		_CheckDuplicateJavaLibraries;
 		_GetAdditionalResourcesFromAssemblies;
 		_CreateAdditionalResourceCache;
+		_DefineBuildTargetAbis;
 	</_CreateBaseApkDependsOnTargets>
 	<_CreateBaseApkInputs>
 		$(MSBuildAllProjects)
@@ -2151,6 +2161,12 @@ because xbuild doesn't support framework reference assemblies.
    <Touch Files="$(_AndroidApkPerAbiFlagFile)" Condition="'$(AndroidCreatePackagePerAbi)' == 'true'" AlwaysCreate="True" />
 </Target>
 
+<Target Name="FilterDesignTimeFacades">
+	<ItemGroup>
+		<_FilteredShrunkFrameworkAssemblies Include="@(_ShrunkFrameworkAssemblies)" Condition="'%(_ShrunkFrameworkAssemblies.ResolvedFrom)' != 'ImplicitlyExpandDesignTimeFacades'" />
+	</ItemGroup>
+</Target>
+
 <PropertyGroup>
 	<_PrepareBuildApkDependsOnTargets>
 		_SetLatestTargetFrameworkVersion;
@@ -2167,6 +2183,7 @@ because xbuild doesn't support framework reference assemblies.
 		_ResolveSatellitePaths;
 		_CheckApkPerAbiFlag
 		;_LintChecks
+		;FilterDesignTimeFacades
 	</_PrepareBuildApkDependsOnTargets>
 </PropertyGroup>
 
@@ -2202,7 +2219,7 @@ because xbuild doesn't support framework reference assemblies.
 	SupportedAbis="$(_BuildTargetAbis)"
 	AndroidSequencePointsMode="$(_SequencePointsMode)"
 	AotAdditionalArguments="$(AndroidAotAdditionalArguments)"
-	ResolvedAssemblies="@(_ResolvedUserAssemblies);@(_ShrunkFrameworkAssemblies)"
+	ResolvedAssemblies="@(_ResolvedUserAssemblies);@(_FilteredShrunkFrameworkAssemblies)"
 	AotOutputDirectory="$(_AndroidAotBinDirectory)"
 	IntermediateAssemblyDir="$(MonoAndroidIntermediateAssemblyDir)"
 	LinkMode="$(AndroidLinkMode)"
@@ -2216,14 +2233,14 @@ because xbuild doesn't support framework reference assemblies.
 	Condition=" '$(AndroidAotMode)' == 'Hybrid' And '$(AotAssemblies)' == 'True' "
 	AndroidAotMode="$(AndroidAotMode)"
 	ToolPath="$(_MonoAndroidToolsDirectory)"
-	ResolvedAssemblies="@(_ResolvedAssemblies)">
+	ResolvedAssemblies="@(_FilteredShrunkFrameworkAssemblies)">
   </CilStrip> 
 
   <!-- Bundle the assemblies into native libraries in the apk -->
   <MakeBundleNativeCodeExternal
 		Condition="'$(BundleAssemblies)' == 'True'"
 		AndroidNdkDirectory="$(_AndroidNdkDirectory)"
-		Assemblies="@(_ResolvedUserAssemblies);@(_AndroidResolvedSatellitePaths);@(_ShrunkFrameworkAssemblies)"
+		Assemblies="@(_ResolvedUserAssemblies);@(_AndroidResolvedSatellitePaths);@(_FilteredShrunkFrameworkAssemblies)"
 		IncludePath="$(MonoAndroidIncludeDirectory)"
 		SupportedAbis="$(_BuildTargetAbis)"
 		TempOutputPath="$(IntermediateOutputPath)"
@@ -2241,7 +2258,7 @@ because xbuild doesn't support framework reference assemblies.
     EmbedAssemblies="$(EmbedAssembliesIntoApk)"
     Environments="@(AndroidEnvironment);@(LibraryEnvironments)"
     ResolvedUserAssemblies="@(_ResolvedUserAssemblies);@(_AndroidResolvedSatellitePaths)"
-    ResolvedFrameworkAssemblies="@(_ShrunkFrameworkAssemblies)"
+    ResolvedFrameworkAssemblies="@(_FilteredShrunkFrameworkAssemblies)"
     NativeLibraries="@(AndroidNativeLibrary)"
     AdditionalNativeLibraryReferences="@(_AdditionalNativeLibraryReferences)"
     EmbeddedNativeLibraryAssemblies="$(OutDir)$(TargetFileName);@(ReferencePath);@(ReferenceDependencyPaths)"