Revert IBuildEngine.ProjectFileOfTaskNode use. (#201)

Reverts: 47f95ab
Reverts: 76c076f

Context: dotnet/android#7685 (comment)

The problem is that we misunderstood
[`IBuildEngine.ProjectFileOfTaskNode`][0]: we *thought* (hoped?) that
it would return `$(MSBuildProjectFullPath)`, the path to the
`.csproj` being built.

In actuality it returns `$(MSBuildThisFileFullPath)` for the file
containing the Task invocation.  Meaning if e.g.
`Xamarin.Android.Common.targets` contains the Task invocation, then
IBuildEngine.ProjectFileOfTaskNode` would be the path to
`Xamarin.Android.Common.targets`, *not* the path of the `.csproj`.

This in turn means it doesn't actually solve the problem we had.

We will instead need to audit all use of
`IBuildEngine4.RegisterTaskObject()` & related to ensure that the
keys provided *also* contain paths to project-specific files,
if necessary.

Revert 47f95ab and 76c076f, as the changes are not needed.

[0]: https://learn.microsoft.com/en-us/dotnet/api/microsoft.build.framework.ibuildengine.projectfileoftasknode?view=msbuild-17-netcore

Author: jonpryor

src/Microsoft.Android.Build.BaseTasks/MSBuildExtensions.cs

@@ -13,12 +13,6 @@
 
 namespace Microsoft.Android.Build.Tasks
 {
-	[Flags]
-	public enum RegisterTaskObjectKeyFlags {
-		None = 0,
-		IncludeProjectFile = 1 << 0,
-	}
-
 	public static class MSBuildExtensions
 	{
 		public static void LogDebugMessage (this TaskLoggingHelper log, string message, params object[] messageArgs)
@@ -259,80 +253,33 @@ public static void SetDestinationSubPath (this ITaskItem assembly)
 		/// IBuildEngine4.RegisterTaskObject, but adds the current assembly path into the key
 		/// </summary>
 		public static void RegisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, object value, RegisteredTaskObjectLifetime lifetime, bool allowEarlyCollection = false) =>
-			RegisterTaskObjectAssemblyLocal (engine, key, value, lifetime, allowEarlyCollection: false, flags: RegisterTaskObjectKeyFlags.IncludeProjectFile);
-
-		/// <summary>
-		/// IBuildEngine4.RegisterTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static void RegisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, object value, RegisteredTaskObjectLifetime lifetime, RegisterTaskObjectKeyFlags flags) =>
-			engine.RegisterTaskObject (engine.GetKey (AssemblyLocation, key, flags), value, lifetime, allowEarlyCollection: false);
-
-		/// <summary>
-		/// IBuildEngine4.RegisterTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static void RegisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, object value, RegisteredTaskObjectLifetime lifetime, bool allowEarlyCollection, RegisterTaskObjectKeyFlags flags) =>
-			engine.RegisterTaskObject (engine.GetKey (AssemblyLocation, key, flags), value, lifetime, allowEarlyCollection);
+			engine.RegisterTaskObject ((AssemblyLocation, key), value, lifetime, allowEarlyCollection);
 
 		/// <summary>
 		/// IBuildEngine4.GetRegisteredTaskObject, but adds the current assembly path into the key
 		/// </summary>
 		public static object GetRegisteredTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime) =>
-			GetRegisteredTaskObjectAssemblyLocal (engine, key, lifetime, flags: RegisterTaskObjectKeyFlags.IncludeProjectFile);
-
-		/// <summary>
-		/// IBuildEngine4.GetRegisteredTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static object GetRegisteredTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime, RegisterTaskObjectKeyFlags flags) =>
-			engine.GetRegisteredTaskObject (engine.GetKey (AssemblyLocation, key, flags), lifetime);
-
+			engine.GetRegisteredTaskObject ((AssemblyLocation, key), lifetime);
 
 		/// <summary>
 		/// Generic version of IBuildEngine4.GetRegisteredTaskObject, but adds the current assembly path into the key
 		/// </summary>
 		public static T GetRegisteredTaskObjectAssemblyLocal<T> (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime)
-			where T : class => GetRegisteredTaskObjectAssemblyLocal<T> (engine, key, lifetime, flags: RegisterTaskObjectKeyFlags.IncludeProjectFile);
-
-		/// <summary>
-		/// Generic version of IBuildEngine4.GetRegisteredTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static T GetRegisteredTaskObjectAssemblyLocal<T> (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime, RegisterTaskObjectKeyFlags flags)
 			where T : class =>
-			engine.GetRegisteredTaskObject (engine.GetKey (AssemblyLocation, key, flags), lifetime) as T;
+			engine.GetRegisteredTaskObject ((AssemblyLocation, key), lifetime) as T;
 
-		/// <summary>
-		/// IBuildEngine4.UnregisterTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static object UnregisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime) =>
-			UnregisterTaskObjectAssemblyLocal (engine, key, lifetime, flags: RegisterTaskObjectKeyFlags.IncludeProjectFile);
 
 		/// <summary>
 		/// IBuildEngine4.UnregisterTaskObject, but adds the current assembly path into the key
 		/// </summary>
-		public static object UnregisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime, RegisterTaskObjectKeyFlags flags) =>
-			engine.UnregisterTaskObject (engine.GetKey (AssemblyLocation, key, flags), lifetime);
+		public static object UnregisterTaskObjectAssemblyLocal (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime) =>
+			engine.UnregisterTaskObject ((AssemblyLocation, key), lifetime);
 
 		/// <summary>
 		/// Generic version of IBuildEngine4.UnregisterTaskObject, but adds the current assembly path into the key
 		/// </summary>
 		public static T UnregisterTaskObjectAssemblyLocal<T> (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime)
-			where T : class => UnregisterTaskObjectAssemblyLocal<T> (engine, key, lifetime, flags: RegisterTaskObjectKeyFlags.IncludeProjectFile);
-
-		/// <summary>
-		/// Generic version of IBuildEngine4.UnregisterTaskObject, but adds the current assembly path into the key
-		/// </summary>
-		public static T UnregisterTaskObjectAssemblyLocal<T> (this IBuildEngine4 engine, object key, RegisteredTaskObjectLifetime lifetime, RegisterTaskObjectKeyFlags flags)
 			where T : class =>
-			engine.UnregisterTaskObject (engine.GetKey (AssemblyLocation, key, flags), lifetime) as T;
-
-		/// <summary>
-		/// Method to calculate the key for the RegisterTaskObject. This is based on the
-		/// RegisterTaskObjectKeyFlags which are passed.
-		/// </summary>
-		static object GetKey (this IBuildEngine4 engine, string location, object key, RegisterTaskObjectKeyFlags flags)
-		{
-			return ((flags & RegisterTaskObjectKeyFlags.IncludeProjectFile) != 0)
-				? (location, key, engine.ProjectFileOfTaskNode)
-				: (location, key, string.Empty);
-		}
+			engine.UnregisterTaskObject ((AssemblyLocation, key), lifetime) as T;
 	}
 }