Use one mutator for all bp2build conversion.

Each conversion required defining a separate mutator, which will each
operate on _all_ modules and requires each to repeat checks whether the
mutator should operator. Instead, we introduce a single mutator and
modules can define a ConvertWithBp2build to implement bp2build
conversion for that module.

Test: bp2build.sh
Bug: 183079158
Change-Id: I99d4b51f441c2903879092c5b56313d606d4338d
diff --git a/python/binary.go b/python/binary.go
index af02de6..99c6259 100644
--- a/python/binary.go
+++ b/python/binary.go
@@ -27,7 +27,6 @@
 
 func init() {
 	registerPythonBinaryComponents(android.InitRegistrationContext)
-	android.RegisterBp2BuildMutator("python_binary_host", PythonBinaryBp2Build)
 }
 
 func registerPythonBinaryComponents(ctx android.RegistrationContext) {
@@ -41,17 +40,7 @@
 	Python_version *string
 }
 
-func PythonBinaryBp2Build(ctx android.TopDownMutatorContext) {
-	m, ok := ctx.Module().(*Module)
-	if !ok || !m.ConvertWithBp2build(ctx) {
-		return
-	}
-
-	// a Module can be something other than a python_binary_host
-	if ctx.ModuleType() != "python_binary_host" {
-		return
-	}
-
+func pythonBinaryBp2Build(ctx android.TopDownMutatorContext, m *Module) {
 	var main *string
 	for _, propIntf := range m.GetProperties() {
 		if props, ok := propIntf.(*BinaryProperties); ok {