codec2: trim log

Bug: 132461433
Test: bug repro steps
Change-Id: Ie79b8948dc2eae773a433d90c23e7b6924bd503e
diff --git a/media/codec2/sfplugin/CCodecConfig.h b/media/codec2/sfplugin/CCodecConfig.h
index 3bafe3f..a61c8b7 100644
--- a/media/codec2/sfplugin/CCodecConfig.h
+++ b/media/codec2/sfplugin/CCodecConfig.h
@@ -134,6 +134,8 @@
     /// For now support a validation function.
     std::map<C2Param::Index, LocalParamValidator> mLocalParams;
 
+    std::set<std::string> mLastConfig;
+
     CCodecConfig();
 
     /// initializes the members required to manage the format: descriptors, reflector,