Fix memory leaks

Bug: 111407253
Test: manual, libmemunreachable
Change-Id: I69ad7b48498346925dd02c10b206035c0ae49305
diff --git a/media/libmediaextractor/MediaBufferGroup.cpp b/media/libmediaextractor/MediaBufferGroup.cpp
index e88ed5a..84ff9a6 100644
--- a/media/libmediaextractor/MediaBufferGroup.cpp
+++ b/media/libmediaextractor/MediaBufferGroup.cpp
@@ -125,6 +125,7 @@
         buffer->release();
     }
     delete mInternal;
+    delete mWrapper;
 }
 
 void MediaBufferGroup::add_buffer(MediaBufferBase *buffer) {