bp2build: block src == name for prebuilt_* modules

src == name causes circular dependency errors, instead mark these as
unconverted and don't create modules for them.

Test: m bp2build and verify boringssl_self_test.zygote64.rc unconverted
Change-Id: I5d5fdd7e14830cd685816064cd0377998d07293c

etc/prebuilt_etc.go

@@ -40,6 +40,7 @@ import (
 	"android/soong/bazel"
 	"android/soong/bazel/cquery"
 	"android/soong/snapshot"
+	"android/soong/ui/metrics/bp2build_metrics_proto"
 )
 
 var pctx = android.NewPackageContext("android/soong/etc")
@@ -711,7 +712,7 @@ type bazelPrebuiltFileAttributes struct {
 // Bp2buildHelper returns a bazelPrebuiltFileAttributes used for the conversion
 // of prebuilt_*  modules. bazelPrebuiltFileAttributes has the common attributes
 // used by both prebuilt_etc_xml and other prebuilt_* moodules
-func (module *PrebuiltEtc) Bp2buildHelper(ctx android.TopDownMutatorContext) *bazelPrebuiltFileAttributes {
+func (module *PrebuiltEtc) Bp2buildHelper(ctx android.TopDownMutatorContext) (*bazelPrebuiltFileAttributes, bool) {
 	var src bazel.LabelAttribute
 	for axis, configToProps := range module.GetArchVariantProperties(ctx, &prebuiltEtcProperties{}) {
 		for config, p := range configToProps {
@@ -720,7 +721,12 @@ func (module *PrebuiltEtc) Bp2buildHelper(ctx android.TopDownMutatorContext) *ba
 				continue
 			}
 			if props.Src != nil {
-				label := android.BazelLabelForModuleSrcSingle(ctx, *props.Src)
+				srcStr := proptools.String(props.Src)
+				if srcStr == ctx.ModuleName() {
+					ctx.MarkBp2buildUnconvertible(bp2build_metrics_proto.UnconvertedReasonType_PROPERTY_UNSUPPORTED, "src == name")
+					return &bazelPrebuiltFileAttributes{}, false
+				}
+				label := android.BazelLabelForModuleSrcSingle(ctx, srcStr)
 				src.SetSelectValue(axis, config, label)
 			}
 		}
@@ -779,8 +785,7 @@ func (module *PrebuiltEtc) Bp2buildHelper(ctx android.TopDownMutatorContext) *ba
 		attrs.Filename_from_src = bazel.BoolAttribute{Value: moduleProps.Filename_from_src}
 	}
 
-	return attrs
-
+	return attrs, true
 }
 
 // ConvertWithBp2build performs bp2build conversion of PrebuiltEtc
@@ -793,7 +798,10 @@ func (module *PrebuiltEtc) ConvertWithBp2build(ctx android.TopDownMutatorContext
 		return
 	}
 
-	attrs := module.Bp2buildHelper(ctx)
+	attrs, convertible := module.Bp2buildHelper(ctx)
+	if !convertible {
+		return
+	}
 
 	props := bazel.BazelTargetModuleProperties{
 		Rule_class:        "prebuilt_file",