Support experimental building with OpenJDK 17 am: 59c1e6ac0e am: 6984e882eb am: a1a1d6051a

Original change: https://android-review.googlesource.com/c/platform/build/soong/+/2006781

Change-Id: Iade0b38332bcca9742ab46284f8e62c088de8830

java/config/config.go

@@ -105,7 +105,12 @@ func init() {
 		if override := ctx.Config().Getenv("OVERRIDE_JLINK_VERSION_NUMBER"); override != "" {
 			return override
 		}
-		return "11"
+		switch ctx.Config().Getenv("EXPERIMENTAL_USE_OPENJDK17_TOOLCHAIN") {
+		case "true":
+			return "17"
+		default:
+			return "11"
+		}
 	})
 
 	pctx.SourcePathVariable("JavaToolchain", "${JavaHome}/bin")