Add unstrippedOutputFilePath to the linker interface

Test: m
Change-Id: I85a0cbda6ebb9838451ed8c607c2087460b7b742
diff --git a/cc/object.go b/cc/object.go
index 552f639..b9c5742 100644
--- a/cc/object.go
+++ b/cc/object.go
@@ -107,3 +107,7 @@
 	ctx.CheckbuildFile(outputFile)
 	return outputFile
 }
+
+func (object *objectLinker) unstrippedOutputFilePath() android.Path {
+	return nil
+}