Remove the out/soong/.bootstrap directory.

It's better not to have state hidden in dotfiles (or rather,
dotdirectories) if we can help.

It's questionable whether the "linux-x86" path segment makes sense since
soong_build only ever runs on one operating system, but I didn't want to
rock the boat now.

Drive-by fixed some quoting fixes in rbc-run. Notably, I didn't wrap
`$@` into double quotes because I don't know whether the lack of double
quotes was intended or not.

Also drive-by fixed the fact that "out/soong" was added twice to the
directory name of bpglob. This turned out not to be a problem because
bpglob doesn't need to be explicitly built: if it's needed, it's
declared as an input of the glob files so it'll be built automatically
(at the cost of the first "null build" not actually being a null build)

Test: Presubmits.
Change-Id: I710d8d16cd8212059a0ca1ee95378505303eed83
diff --git a/ui/build/config.go b/ui/build/config.go
index 07ffb44..e0fa503 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -784,12 +784,13 @@
 		panic("Unknown GOOS")
 	}
 }
+
 func (c *configImpl) HostToolDir() string {
 	return filepath.Join(c.SoongOutDir(), "host", c.PrebuiltOS(), "bin")
 }
 
 func (c *configImpl) NamedGlobFile(name string) string {
-	return shared.JoinPath(c.SoongOutDir(), ".bootstrap/build-globs."+name+".ninja")
+	return shared.JoinPath(c.SoongOutDir(), "globs-"+name+".ninja")
 }
 
 func (c *configImpl) UsedEnvFile(tag string) string {
@@ -797,7 +798,7 @@
 }
 
 func (c *configImpl) Bp2BuildMarkerFile() string {
-	return shared.JoinPath(c.SoongOutDir(), ".bootstrap/bp2build_workspace_marker")
+	return shared.JoinPath(c.SoongOutDir(), "bp2build_workspace_marker")
 }
 
 func (c *configImpl) SoongDocsHtml() string {
diff --git a/ui/build/dumpvars.go b/ui/build/dumpvars.go
index afec829..3f10f75 100644
--- a/ui/build/dumpvars.go
+++ b/ui/build/dumpvars.go
@@ -263,9 +263,9 @@
 	}, exportEnvVars...), BannerVars...)
 
 	// We need Roboleaf converter and runner in the mixed mode
-	runMicrofactory(ctx, config, ".bootstrap/bin/mk2rbc", "android/soong/mk2rbc/cmd",
+	runMicrofactory(ctx, config, "mk2rbc", "android/soong/mk2rbc/cmd",
 		map[string]string{"android/soong": "build/soong"})
-	runMicrofactory(ctx, config, ".bootstrap/bin/rbcrun", "rbcrun/cmd",
+	runMicrofactory(ctx, config, "rbcrun", "rbcrun/cmd",
 		map[string]string{"go.starlark.net": "external/starlark-go", "rbcrun": "build/make/tools/rbcrun"})
 
 	makeVars, err := dumpMakeVars(ctx, config, config.Arguments(), allVars, true, "")
diff --git a/ui/build/soong.go b/ui/build/soong.go
index 1c7fbac..c7e1435 100644
--- a/ui/build/soong.go
+++ b/ui/build/soong.go
@@ -292,7 +292,7 @@
 	var blueprintArgs bootstrap.Args
 
 	blueprintArgs.ModuleListFile = filepath.Join(config.FileListDir(), "Android.bp.list")
-	blueprintArgs.OutFile = shared.JoinPath(config.SoongOutDir(), ".bootstrap/build.ninja")
+	blueprintArgs.OutFile = shared.JoinPath(config.SoongOutDir(), "bootstrap.ninja")
 	blueprintArgs.EmptyNinjaFile = false
 
 	blueprintCtx := blueprint.NewContext()
@@ -314,7 +314,7 @@
 	}
 
 	bootstrapDeps := bootstrap.RunBlueprint(blueprintArgs, bootstrap.DoEverything, blueprintCtx, blueprintConfig)
-	bootstrapDepFile := shared.JoinPath(config.SoongOutDir(), ".bootstrap/build.ninja.d")
+	bootstrapDepFile := shared.JoinPath(config.SoongOutDir(), "bootstrap.ninja.d")
 	err := deptools.WriteDepFile(bootstrapDepFile, blueprintArgs.OutFile, bootstrapDeps)
 	if err != nil {
 		ctx.Fatalf("Error writing depfile '%s': %s", bootstrapDepFile, err)
@@ -342,11 +342,6 @@
 	// unused variables were changed?
 	envFile := filepath.Join(config.SoongOutDir(), availableEnvFile)
 
-	dir := filepath.Join(config.SoongOutDir(), ".bootstrap")
-	if err := os.MkdirAll(dir, 0755); err != nil {
-		ctx.Fatalf("Cannot mkdir " + dir)
-	}
-
 	buildMode := config.bazelBuildMode()
 	integratedBp2Build := buildMode == mixedBuild
 
@@ -457,7 +452,7 @@
 		targets = append(targets, config.SoongNinjaFile())
 	}
 
-	ninja("bootstrap", ".bootstrap/build.ninja", targets...)
+	ninja("bootstrap", "bootstrap.ninja", targets...)
 
 	var soongBuildMetrics *soong_metrics_proto.SoongBuildMetrics
 	if shouldCollectBuildSoongMetrics(config) {
@@ -477,8 +472,7 @@
 	}
 }
 
-func runMicrofactory(ctx Context, config Config, relExePath string, pkg string, mapping map[string]string) {
-	name := filepath.Base(relExePath)
+func runMicrofactory(ctx Context, config Config, name string, pkg string, mapping map[string]string) {
 	ctx.BeginTrace(metrics.RunSoong, name)
 	defer ctx.EndTrace()
 	cfg := microfactory.Config{TrimPath: absPath(ctx, ".")}
@@ -486,7 +480,7 @@
 		cfg.Map(pkgPrefix, pathPrefix)
 	}
 
-	exePath := filepath.Join(config.SoongOutDir(), relExePath)
+	exePath := filepath.Join(config.SoongOutDir(), name)
 	dir := filepath.Dir(exePath)
 	if err := os.MkdirAll(dir, 0777); err != nil {
 		ctx.Fatalf("cannot create %s: %s", dir, err)
diff --git a/ui/build/test_build.go b/ui/build/test_build.go
index f9a60b6..83007be 100644
--- a/ui/build/test_build.go
+++ b/ui/build/test_build.go
@@ -63,7 +63,6 @@
 	cmd.StartOrFatal()
 
 	outDir := config.OutDir()
-	bootstrapDir := filepath.Join(outDir, "soong", ".bootstrap")
 	modulePathsDir := filepath.Join(outDir, ".module_paths")
 	variablesFilePath := filepath.Join(outDir, "soong", "soong.variables")
 
@@ -86,8 +85,7 @@
 			// Leaf node is not in the out directory.
 			continue
 		}
-		if strings.HasPrefix(line, bootstrapDir) ||
-			strings.HasPrefix(line, modulePathsDir) ||
+		if strings.HasPrefix(line, modulePathsDir) ||
 			line == variablesFilePath ||
 			line == dexpreoptConfigFilePath ||
 			line == buildDatetimeFilePath {