Fix the default ownership of dex files in ClassLoaderContext

By default the context should have the ownership.

Test: valgrind --leak-check=full
../out/host/linux-x86/nativetest/art_runtime_tests/class_loader_context_test
Bug: 38138251

Change-Id: I21ff048018abba61999b6025281c73fc9899cae0
1 file changed