Strip relative paths from android_library_import output files

androidx.annotation_annotation is used as a test data file, and
converting it from an android_library to an android_library_import
causes the relative path used in the test data path to change.
Clear the relative path in android_library_import the same way that
android_library and other java based modules do.

Also change the name of classes-combined.jar to the name of the
module so that the output file has the right name if there are no
static dependences that require running the merge_zips step.

Bug: 288358614
Test: TestAndroidLibraryOutputFileRel
Change-Id: I28210aa370a742d789102ff71db3685ca744878f
diff --git a/java/aar.go b/java/aar.go
index 1734da9..5a478d0 100644
--- a/java/aar.go
+++ b/java/aar.go
@@ -1154,7 +1154,7 @@
 	}
 
 	extractedAARDir := android.PathForModuleOut(ctx, "aar")
-	classpathFile := extractedAARDir.Join(ctx, "classes-combined.jar")
+	classpathFile := extractedAARDir.Join(ctx, ctx.ModuleName()+".jar")
 	a.manifest = extractedAARDir.Join(ctx, "AndroidManifest.xml")
 	a.rTxt = extractedAARDir.Join(ctx, "R.txt")
 	a.assetsPackage = android.PathForModuleOut(ctx, "assets.zip")
@@ -1276,14 +1276,18 @@
 		addCLCFromDep(ctx, module, a.classLoaderContexts)
 	})
 
+	var implementationJarFile android.OutputPath
 	if len(staticJars) > 0 {
 		combineJars := append(android.Paths{classpathFile}, staticJars...)
-		a.implementationJarFile = android.PathForModuleOut(ctx, "combined", ctx.ModuleName()+".jar")
-		TransformJarsToJar(ctx, a.implementationJarFile, "combine", combineJars, android.OptionalPath{}, false, nil, nil)
+		implementationJarFile = android.PathForModuleOut(ctx, "combined", ctx.ModuleName()+".jar").OutputPath
+		TransformJarsToJar(ctx, implementationJarFile, "combine", combineJars, android.OptionalPath{}, false, nil, nil)
 	} else {
-		a.implementationJarFile = classpathFile
+		implementationJarFile = classpathFile
 	}
 
+	// Save the output file with no relative path so that it doesn't end up in a subdirectory when used as a resource
+	a.implementationJarFile = implementationJarFile.WithoutRel()
+
 	if len(staticHeaderJars) > 0 {
 		combineJars := append(android.Paths{classpathFile}, staticHeaderJars...)
 		a.headerJarFile = android.PathForModuleOut(ctx, "turbine-combined", ctx.ModuleName()+".jar")