Merge "Allow experimental Java target 21 by default" into main

java/java.go

@@ -567,6 +567,12 @@ func getJavaVersion(ctx android.ModuleContext, javaVersion string, sdkContext an
 		return normalizeJavaVersion(ctx, javaVersion)
 	} else if ctx.Device() {
 		return defaultJavaLanguageVersion(ctx, sdkContext.SdkVersion(ctx))
+	} else if ctx.Config().TargetsJava21() {
+		// Temporary experimental flag to be able to try and build with
+		// java version 21 options.  The flag, if used, just sets Java
+		// 21 as the default version, leaving any components that
+		// target an older version intact.
+		return JAVA_VERSION_21
 	} else {
 		return JAVA_VERSION_17
 	}