JDK-8350209 regressed CDS support for Shenandoah a bit.

$ JTREG_KEYWORDS=\!external-dep CONF=linux-x86_64-server-fastdebug make images test TEST=runtime/cds TEST_VM_OPTS="-XX:+UseShenandoahGC"

#
# Internal Error (/home/shade/trunks/jdk/src/hotspot/share/code/aotCodeCache.cpp:1285), pid=285085, tid=285092
# fatal error: Address 0x00007662de27a5b0 for runtime target 'ShenandoahRuntime::load_reference_barrier_phantom(oopDesc*, oop*)+0' is missing in AOT Code Cache addresses table

Current thread (0x00007662d80bbae0): JavaThread "Unknown thread" [_thread_in_vm, id=285092, stack(0x00007662dc700000,0x00007662dc800000) (1024K)]

Stack: [0x00007662dc700000,0x00007662dc800000], sp=0x00007662dc7fc270, free space=1008k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x6a0336] AOTCodeAddressTable::id_for_address(unsigned char*, RelocIterator, CodeBlob*) [clone .part.0]+0x626 (aotCodeCache.cpp:1285)
V [libjvm.so+0x6a0b1d] AOTCodeCache::write_relocations(CodeBlob&)+0x5cd (aotCodeCache.cpp:1243)
V [libjvm.so+0x6a1677] AOTCodeCache::store_code_blob(CodeBlob&, AOTCodeEntry::Kind, unsigned int, char const*, int, int*)+0x427 (aotCodeCache.cpp:719)
V [libjvm.so+0x18f5334] AdapterHandlerLibrary::generate_adapter_code(AdapterBlob*&, AdapterHandlerEntry*, int, BasicType*, bool)+0x4d4 (sharedRuntime.cpp:2852)
V [libjvm.so+0x18f5644] AdapterHandlerLibrary::create_adapter(AdapterBlob*&, int, BasicType*, bool)+0x2b4 (sharedRuntime.cpp:2871)
V [libjvm.so+0x18f6695] AdapterHandlerLibrary::initialize()+0x205 (sharedRuntime.cpp:2585)
V [libjvm.so+0xff7ad7] init_globals()+0x97 (init.cpp:161)
V [libjvm.so+0x1c936b8] Threads::create_vm(JavaVMInitArgs*, bool*)+0x358 (threads.cpp:589)
V [libjvm.so+0x11987a8] JNI_CreateJavaVM+0x58 (jni.cpp:3587)
C [libjli.so+0x4213] JavaMain+0x93 (java.c:1506)
C [libjli.so+0x809d] ThreadJavaMain+0xd (java_md.c:646)
C [libc.so.6+0x9caa4]