[Graal] FieldAccessWatch.java gets assert with jvmci compiler

The test serviceability/jvmti/FieldAccessWatch/FieldAccessWatch.java crashes with an Invalid JNI handle with JVMCI. I think this is intermittent because I couldn't reproduce it locally.

"class: Ljava/util/ArrayList; method: add(TE;)Z" accessed field: "size", location: 17
# To suppress the following error report, specify this argument
# after -XX: or in .hotspotrc: SuppressErrorAt=/jniHandles.inline.hpp:63
#
# A fatal error has been detected by the Java Runtime Environment:
#
# Internal Error (/scratch/opt/mach5/mesos/work_dir/slaves/c4ee7e63-1ded-4e8c-9581-ce26f27e3af4-S541/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/179832eb-811e-424c-95a4-64895edf29fe/runs/21e6117a-9d8a-42e4-a885-91e23264c8c1/workspace/open/src/hotspot/share/runtime/jniHandles.inline.hpp:63), pid=25553, tid=25574
# assert(external_guard || result != __null) failed: Invalid JNI handle
#
# JRE version: Java(TM) SE Runtime Environment (11.0) (fastdebug build 11-internal+0-2018-04-30-1549452.coleen.phillimore.11clean)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 11-internal+0-2018-04-30-1549452.coleen.phillimore.11clean, mixed mode, tiered, jvmci, jvmci compiler, compressed oops, g1 gc, linux-amd64)

Current CompileTask:
JVMCI: 2691 109 4 java.lang.String::charAt (25 bytes)

Stack: [0x00007fc234f7b000,0x00007fc23507c000], sp=0x00007fc235078cb0, free space=1015k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x184b56f] VMError::report_and_die(int, char const*, char const*, __va_list_tag*, Thread*, unsigned char*, void*, void*, char const*, int, unsigned long)+0x25f
V [libjvm.so+0x184c32f] VMError::report_and_die(Thread*, void*, char const*, int, char const*, char const*, __va_list_tag*)+0x2f
V [libjvm.so+0xade400] report_vm_error(char const*, int, char const*, char const*, ...)+0x100
V [libjvm.so+0xa4c0ff] JNIHandles::resolve_non_null(_jobject*)+0x13f
V [libjvm.so+0xfb11df] jni_SetBooleanField+0x16f
C [libFieldAccessWatch.so+0xb11] handleNotification+0x1c1
V [libjvm.so+0x1178186] JvmtiExport::post_field_access(JavaThread*, Method*, unsigned char*, Klass*, Handle, _jfieldID*)+0x126
V [libjvm.so+0xe8e444] InterpreterRuntime::post_field_access(JavaThread*, oopDesc*, ConstantPoolCacheEntry*)+0x3a4
j java.util.ArrayList.add(Ljava/lang/Object;)Z+17 java.base@11-internal
j jdk.vm.ci.hotspot.HotSpotSignature.<init>(Ljdk/vm/ci/hotspot/HotSpotJVMCIRuntimeProvider;Ljava/lang/String;)V+90 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotConstantPool.lookupSignature(I)Ljdk/vm/ci/meta/Signature;+12 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotResolvedJavaMethodImpl.<init>(Ljdk/vm/ci/hotspot/HotSpotResolvedObjectTypeImpl;J)V+101 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotResolvedObjectTypeImpl.createMethod(J)Ljdk/vm/ci/hotspot/HotSpotResolvedJavaMethod;+46 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotResolvedJavaMethodImpl.fromMetaspace(J)Ljdk/vm/ci/hotspot/HotSpotResolvedJavaMethod;+7 jdk.internal.vm.ci@11-internal
v ~StubRoutines::call_stub
V [libjvm.so+0xeb5b4a] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, Thread*)+0x85a
V [libjvm.so+0xeb3841] JavaCalls::call_static(JavaValue*, Klass*, Symbol*, Symbol*, JavaCallArguments*, Thread*)+0x1a1
V [libjvm.so+0x1066192] CompilerToVM::get_jvmci_method(methodHandle const&, Thread*)+0xc2
V [libjvm.so+0x106b1b8] c2v_asResolvedJavaMethod(JNIEnv_*, _jobject*, _jobject*)+0x248
j jdk.vm.ci.hotspot.CompilerToVM.asResolvedJavaMethod(Ljava/lang/reflect/Executable;)Ljdk/vm/ci/hotspot/HotSpotResolvedJavaMethodImpl;+0 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotMetaAccessProvider.lookupJavaMethod(Ljava/lang/reflect/Executable;)Ljdk/vm/ci/meta/ResolvedJavaMethod;+16 jdk.internal.vm.ci@11-internal
j org.graalvm.compiler.hotspot.stubs.SnippetStub.<init>(Ljava/lang/Class;Ljava/lang/String;Lorg/graalvm/compiler/options/OptionValues;Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/hotspot/HotSpotForeignCallLinkage;)V+36 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.stubs.SnippetStub.<init>(Ljava/lang/String;Lorg/graalvm/compiler/options/OptionValues;Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/hotspot/HotSpotForeignCallLinkage;)V+7 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.stubs.CreateExceptionStub.<init>(Ljava/lang/String;Lorg/graalvm/compiler/options/OptionValues;Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/hotspot/HotSpotForeignCallLinkage;)V+6 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.stubs.ClassCastExceptionStub.<init>(Lorg/graalvm/compiler/options/OptionValues;Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/hotspot/HotSpotForeignCallLinkage;)V+6 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.meta.HotSpotHostForeignCallsProvider.initialize(Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/options/OptionValues;)V+820 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.amd64.AMD64HotSpotForeignCallsProvider.initialize(Lorg/graalvm/compiler/hotspot/meta/HotSpotProviders;Lorg/graalvm/compiler/options/OptionValues;)V+440 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.HotSpotHostBackend.completeInitialization(Ljdk/vm/ci/hotspot/HotSpotJVMCIRuntime;Lorg/graalvm/compiler/options/OptionValues;)V+34 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.HotSpotGraalRuntime.<init>(Ljava/lang/String;Ljdk/vm/ci/hotspot/HotSpotJVMCIRuntime;Lorg/graalvm/compiler/hotspot/CompilerConfigurationFactory;Lorg/graalvm/compiler/options/OptionValues;)V+663 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.HotSpotGraalCompilerFactory.createCompiler(Ljava/lang/String;Ljdk/vm/ci/runtime/JVMCIRuntime;Lorg/graalvm/compiler/options/OptionValues;Lorg/graalvm/compiler/hotspot/CompilerConfigurationFactory;)Lorg/graalvm/compiler/hotspot/HotSpotGraalCompiler;+22 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.HotSpotGraalCompilerFactory.createCompiler(Ljdk/vm/ci/runtime/JVMCIRuntime;)Lorg/graalvm/compiler/hotspot/HotSpotGraalCompiler;+32 jdk.internal.vm.compiler@11-internal
j org.graalvm.compiler.hotspot.HotSpotGraalCompilerFactory.createCompiler(Ljdk/vm/ci/runtime/JVMCIRuntime;)Ljdk/vm/ci/runtime/JVMCICompiler;+2 jdk.internal.vm.compiler@11-internal
j jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.getCompiler()Ljdk/vm/ci/runtime/JVMCICompiler;+24 jdk.internal.vm.ci@11-internal
j jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.compileMethod(Ljdk/vm/ci/hotspot/HotSpotResolvedJavaMethod;IJI)Ljdk/vm/ci/hotspot/HotSpotCompilationRequestResult;+1 jdk.internal.vm.ci@11-internal
v ~StubRoutines::call_stub
V [libjvm.so+0xeb5b4a] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, Thread*)+0x85a
V [libjvm.so+0xeb2c9a] JavaCalls::call_special(JavaValue*, Klass*, Symbol*, Symbol*, JavaCallArguments*, Thread*)+0x27a
V [libjvm.so+0x10623c9] JVMCICompiler::compile_method(methodHandle const&, int, JVMCIEnv*)+0x789
V [libjvm.so+0xa4b885] CompileBroker::invoke_compiler_on_method(CompileTask*)+0x1055
V [libjvm.so+0xa4bc17] CompileBroker::compiler_thread_loop()+0x317
V [libjvm.so+0x1796207] JavaThread::thread_main_inner()+0x2c7
V [libjvm.so+0x179655f] JavaThread::run()+0x24f
V [libjvm.so+0x14a9e00] thread_native_entry(Thread*)+0x100