Move bazel.Properties to a BazelModuleBase

This allows more direct access to the bazel label and whether the module
is bp2build available.

Test: go test *
Change-Id: I23375835d20fa53d7d94127b2dc2d5bb20487bfb

android/filegroup.go

@@ -49,7 +49,7 @@ func (bfg *bazelFilegroup) GenerateAndroidBuildActions(ctx ModuleContext) {}
 
 func FilegroupBp2Build(ctx TopDownMutatorContext) {
 	fg, ok := ctx.Module().(*fileGroup)
-	if !ok || !fg.properties.Bazel_module.Bp2build_available {
+	if !ok || !fg.ConvertWithBp2build() {
 		return
 	}
 
@@ -77,13 +77,11 @@ type fileGroupProperties struct {
 	// Create a make variable with the specified name that contains the list of files in the
 	// filegroup, relative to the root of the source tree.
 	Export_to_make_var *string
-
-	// Properties for Bazel migration purposes.
-	bazel.Properties
 }
 
 type fileGroup struct {
 	ModuleBase
+	BazelModuleBase
 	properties fileGroupProperties
 	srcs       Paths
 }
@@ -97,6 +95,7 @@ func FileGroupFactory() Module {
 	module := &fileGroup{}
 	module.AddProperties(&module.properties)
 	InitAndroidModule(module)
+	InitBazelModule(module)
 	return module
 }