Add TestingBuildParams.RelativeToTop()

The methods returns a copy of TestingBuildParams with every usage of a
path that is relative to the temporary test build directory with a path
relative to a notional top. Similar to how PathRelativeToTop does.

Bug: 182885307
Test: m nothing
Change-Id: I6ec20fc52ed76748138f0d48b4df80f765dfcfdc
diff --git a/android/rule_builder_test.go b/android/rule_builder_test.go
index f41d61b..9cd60a2 100644
--- a/android/rule_builder_test.go
+++ b/android/rule_builder_test.go
@@ -562,46 +562,44 @@
 		AssertBoolEquals(t, "RuleParams.Restat", wantRestat, params.RuleParams.Restat)
 
 		wantImplicits := append([]string{"bar"}, extraImplicits...)
-		AssertArrayString(t, "Implicits", wantImplicits, params.Implicits.Strings())
+		AssertPathsRelativeToTopEquals(t, "Implicits", wantImplicits, params.Implicits)
 
-		AssertStringEquals(t, "Output", wantOutput, params.Output.String())
+		AssertPathRelativeToTopEquals(t, "Output", wantOutput, params.Output)
 
 		if len(params.ImplicitOutputs) != 0 {
 			t.Errorf("want ImplicitOutputs = [], got %q", params.ImplicitOutputs.Strings())
 		}
 
-		AssertStringEquals(t, "Depfile", wantDepfile, params.Depfile.String())
+		AssertPathRelativeToTopEquals(t, "Depfile", wantDepfile, params.Depfile)
 
 		if params.Deps != blueprint.DepsGCC {
 			t.Errorf("want Deps = %q, got %q", blueprint.DepsGCC, params.Deps)
 		}
 	}
 
-	buildDir := result.Config.BuildDir()
-
 	t.Run("module", func(t *testing.T) {
-		outFile := filepath.Join(buildDir, ".intermediates", "foo", "gen", "foo")
-		check(t, result.ModuleForTests("foo", "").Rule("rule"),
+		outFile := "out/soong/.intermediates/foo/gen/foo"
+		check(t, result.ModuleForTests("foo", "").Rule("rule").RelativeToTop(),
 			"cp bar "+outFile,
 			outFile, outFile+".d", true, nil, nil)
 	})
 	t.Run("sbox", func(t *testing.T) {
-		outDir := filepath.Join(buildDir, ".intermediates", "foo_sbox")
+		outDir := "out/soong/.intermediates/foo_sbox"
 		outFile := filepath.Join(outDir, "gen/foo_sbox")
 		depFile := filepath.Join(outDir, "gen/foo_sbox.d")
 		manifest := filepath.Join(outDir, "sbox.textproto")
-		sbox := filepath.Join(buildDir, "host", result.Config.PrebuiltOS(), "bin/sbox")
-		sandboxPath := shared.TempDirForOutDir(buildDir)
+		sbox := filepath.Join("out", "soong", "host", result.Config.PrebuiltOS(), "bin/sbox")
+		sandboxPath := shared.TempDirForOutDir("out/soong")
 
 		cmd := `rm -rf ` + outDir + `/gen && ` +
 			sbox + ` --sandbox-path ` + sandboxPath + ` --manifest ` + manifest
 
-		check(t, result.ModuleForTests("foo_sbox", "").Output("gen/foo_sbox"),
+		check(t, result.ModuleForTests("foo_sbox", "").Output("gen/foo_sbox").RelativeToTop(),
 			cmd, outFile, depFile, false, []string{manifest}, []string{sbox})
 	})
 	t.Run("singleton", func(t *testing.T) {
-		outFile := filepath.Join(buildDir, "singleton/gen/baz")
-		check(t, result.SingletonForTests("rule_builder_test").Rule("rule"),
+		outFile := filepath.Join("out/soong/singleton/gen/baz")
+		check(t, result.SingletonForTests("rule_builder_test").Rule("rule").RelativeToTop(),
 			"cp bar "+outFile, outFile, outFile+".d", true, nil, nil)
 	})
 }