8210194: [TESTBUG] jvmti_FollowRefObjects.cpp missing initializer for member _jvmtiHeapCallbacks::heap_reference_callback

Backport-of: 3c135ae

Author: shipilev

test/hotspot/jtreg/vmTestbase/nsk/jvmti/unit/FollowReferences/followref001/followref001.cpp

@@ -69,7 +69,7 @@ static const jlong CHAIN_CLASS_TAG  = 99;
 static const jlong ROOT_OBJECT_TAG  = 10;
 static const jlong CHAIN_OBJECT_TAG = 100;
 
-static jvmtiHeapCallbacks heapCallbacks = {};
+static jvmtiHeapCallbacks heapCallbacks;
 
 /* This array has to be up-to-date with the jvmtiHeapReferenceKind enum */
 static const char* ref_kind_str[28] = {

test/hotspot/jtreg/vmTestbase/nsk/jvmti/unit/FollowReferences/followref002/followref002.cpp

@@ -67,7 +67,7 @@ static jlong chainClassTag  = 99;
 static jlong rootObjectTag  = 10;
 static jlong chainObjectTag = 100;
 
-static jvmtiHeapCallbacks heapCallbacks = {};
+static jvmtiHeapCallbacks heapCallbacks;
 
 static const char* ref_kind_str[28] = {
    "unknown_0",

test/hotspot/jtreg/vmTestbase/nsk/jvmti/unit/FollowReferences/followref003/followref003.cpp

@@ -92,7 +92,7 @@ static jlong chainObjectTag = 100;
 #define DUMMY_STRING_ARR_SLOT  11
 
 
-static jvmtiHeapCallbacks heapCallbacks = {};
+static jvmtiHeapCallbacks heapCallbacks;
 
 static const char* ref_kind_str[28] = {
    "unknown_0",

test/hotspot/jtreg/vmTestbase/nsk/share/jvmti/jvmti_FollowRefObjects.cpp

@@ -33,7 +33,7 @@ extern "C" {
 
 int g_fakeUserData = 0;
 int g_userDataError = 0;
-jvmtiHeapCallbacks g_wrongHeapCallbacks = {};
+jvmtiHeapCallbacks g_wrongHeapCallbacks;
 
 /* This array has to be up-to-date with the jvmtiHeapReferenceKind enum */
 const char * const g_refKindStr[28] = {