Revert "Sandbox soong_build by changing to root directory"

This reverts commit 05c25ccb4a.

Reason for revert: broke absolute OUT_DIR
Bug: 146437378

Change-Id: I523ed79d40e1c1ef040212ba794a7a084abea75d

android/config.go

@@ -135,12 +135,12 @@ type jsonConfigurable interface {
 }
 
 func loadConfig(config *config) error {
-	err := loadFromConfigFile(&config.FileConfigurableOptions, absolutePath(config.ConfigFileName))
+	err := loadFromConfigFile(&config.FileConfigurableOptions, config.ConfigFileName)
 	if err != nil {
 		return err
 	}
 
-	return loadFromConfigFile(&config.productVariables, absolutePath(config.ProductVariablesFileName))
+	return loadFromConfigFile(&config.productVariables, config.ProductVariablesFileName)
 }
 
 // loads configuration options from a JSON file in the cwd.
@@ -204,17 +204,6 @@ func saveToConfigFile(config jsonConfigurable, filename string) error {
 	return nil
 }
 
-// NullConfig returns a mostly empty Config for use by standalone tools like dexpreopt_gen that
-// use the android package.
-func NullConfig(buildDir string) Config {
-	return Config{
-		config: &config{
-			buildDir: buildDir,
-			fs:       pathtools.OsFs,
-		},
-	}
-}
-
 // TestConfig returns a Config object suitable for using for tests
 func TestConfig(buildDir string, env map[string]string, bp string, fs map[string][]byte) Config {
 	envCopy := make(map[string]string)
@@ -331,7 +320,7 @@ func NewConfig(srcDir, buildDir string) (Config, error) {
 		buildDir:          buildDir,
 		multilibConflicts: make(map[ArchType]bool),
 
-		fs: pathtools.NewOsFs(absSrcDir),
+		fs: pathtools.OsFs,
 	}
 
 	config.deviceConfig = &deviceConfig{
@@ -361,7 +350,7 @@ func NewConfig(srcDir, buildDir string) (Config, error) {
 	}
 
 	inMakeFile := filepath.Join(buildDir, ".soong.in_make")
-	if _, err := os.Stat(absolutePath(inMakeFile)); err == nil {
+	if _, err := os.Stat(inMakeFile); err == nil {
 		config.inMake = true
 	}
 
@@ -409,8 +398,6 @@ func NewConfig(srcDir, buildDir string) (Config, error) {
 	return Config{config}, nil
 }
 
-var TestConfigOsFs = map[string][]byte{}
-
 // mockFileSystem replaces all reads with accesses to the provided map of
 // filenames to contents stored as a byte slice.
 func (c *config) mockFileSystem(bp string, fs map[string][]byte) {
@@ -914,13 +901,8 @@ func (c *config) BootJars() []string {
 	return c.productVariables.BootJars
 }
 
-func (c *config) DexpreoptGlobalConfig(ctx PathContext) ([]byte, error) {
-	if c.productVariables.DexpreoptGlobalConfig == nil {
-		return nil, nil
-	}
-	path := absolutePath(*c.productVariables.DexpreoptGlobalConfig)
-	ctx.AddNinjaFileDeps(path)
-	return ioutil.ReadFile(path)
+func (c *config) DexpreoptGlobalConfig() string {
+	return String(c.productVariables.DexpreoptGlobalConfig)
 }
 
 func (c *config) FrameworksBaseDirExists(ctx PathContext) bool {