AAPT2: Fix references to private parent

Change-Id: Id4697551b6c8cb6167f562de593006ae3c6158c0
diff --git a/tools/aapt2/java/ProguardRules.cpp b/tools/aapt2/java/ProguardRules.cpp
index c096854..c610bb0 100644
--- a/tools/aapt2/java/ProguardRules.cpp
+++ b/tools/aapt2/java/ProguardRules.cpp
@@ -227,14 +227,14 @@
 bool writeKeepSet(std::ostream* out, const KeepSet& keepSet) {
     for (const auto& entry : keepSet.mKeepSet) {
         for (const Source& source : entry.second) {
-            *out << "// Referenced at " << source << "\n";
+            *out << "# Referenced at " << source << "\n";
         }
         *out << "-keep class " << entry.first << " { <init>(...); }\n" << std::endl;
     }
 
     for (const auto& entry : keepSet.mKeepMethodSet) {
         for (const Source& source : entry.second) {
-            *out << "// Referenced at " << source << "\n";
+            *out << "# Referenced at " << source << "\n";
         }
         *out << "-keepclassmembers class * { *** " << entry.first << "(...); }\n" << std::endl;
     }