product_variables srcs in prebuilt_etc

bp2build conversion handles product_variable srcs

bug: 228353067
Test: prebuilt_etc_conversion_test.go
Change-Id: I82d3a384ee14d4e981d502dd9eb824c87d5ae2c7
diff --git a/etc/prebuilt_etc.go b/etc/prebuilt_etc.go
index b2361ce..7520f58 100644
--- a/etc/prebuilt_etc.go
+++ b/etc/prebuilt_etc.go
@@ -31,6 +31,7 @@
 	"encoding/json"
 	"fmt"
 	"path/filepath"
+	"reflect"
 	"strings"
 
 	"github.com/google/blueprint/proptools"
@@ -692,6 +693,22 @@
 				src.SetSelectValue(axis, config, label)
 			}
 		}
+
+		for propName, productConfigProps := range android.ProductVariableProperties(ctx) {
+			for configProp, propVal := range productConfigProps {
+				if propName == "Src" {
+					props, ok := propVal.(*string)
+					if !ok {
+						ctx.PropertyErrorf(" Expected Property to have type string, but was %s\n", reflect.TypeOf(propVal).String())
+						continue
+					}
+					if props != nil {
+						label := android.BazelLabelForModuleSrcSingle(ctx, *props)
+						src.SetSelectValue(configProp.ConfigurationAxis(), configProp.SelectKey(), label)
+					}
+				}
+			}
+		}
 	}
 
 	var filename string