touchbar: fixed IDEA-208708 JVM crashes when creating vcs diff window

native/MacTouchBar/src/TouchBar.m

@@ -30,7 +30,7 @@
 
     NSTouchBarItem * result = (*_jcreator)([identifier UTF8String]);
     if (result == nil)
-        nserror(@"tb [%@]: can't make item for uid '%@'", identifier);
+        nserror(@"tb [%@]: can't make item for uid '%@'", self.name, identifier);
     return result;
 }
 

platform/platform-impl/src/com/intellij/ui/mac/touchbar/NST.java

@@ -156,8 +156,8 @@ public class NST {
     return scrubberNativePeer;
   }
 
-  public static ID createGroupItem(String uid, ID[] items, int count) {
-    return ourNSTLibrary.createGroupItem(uid, items, count); // called from AppKit, uses per-event autorelease-pool
+  public static ID createGroupItem(String uid, ID[] items) {
+    return ourNSTLibrary.createGroupItem(uid, items == null || items.length == 0 ? null : items, items.length); // called from AppKit, uses per-event autorelease-pool
   }
 
   public static void updateButton(ID buttonObj,

platform/platform-impl/src/com/intellij/ui/mac/touchbar/TBItemGroup.java

@@ -26,7 +26,7 @@ class TBItemGroup extends TBItem {
       return ID.NIL;
 
     final ID[] ids = myGroupItems.getVisibleNativePeers();
-    return NST.createGroupItem(myUid, ids, ids.length);
+    return NST.createGroupItem(myUid, ids);
   }
 
   @Override