Remove unused intermediates parameter from ExistentPathForSource

Test: m checkbuild
Change-Id: Id2c0a5039c2ec3b3795385c135ffec022ccd691e
diff --git a/android/package_ctx.go b/android/package_ctx.go
index 0dbcea5..849eb72 100644
--- a/android/package_ctx.go
+++ b/android/package_ctx.go
@@ -240,7 +240,7 @@
 
 	return p.VariableFunc(name, func(config Config) (string, error) {
 		ctx := &configErrorWrapper{p, config, []error{}}
-		paths := ExistentPathsForSources(ctx, "", paths)
+		paths := ExistentPathsForSources(ctx, paths)
 		if len(ctx.errors) > 0 {
 			return "", ctx.errors[0]
 		}