GEODE-10092: add more logging for future debug when region size gets …

…below 0. (apache#7402)

(cherry picked from commit 5ed8bd9)

geode-core/src/main/java/org/apache/geode/internal/cache/LocalRegion.java

@@ -2111,9 +2111,20 @@ public int getRegionSize() {
       // if this is a client with no tombstones then we subtract the number
       // of entries being affected by register-interest refresh
       if (imageState.isClient() && !getConcurrencyChecksEnabled()) {
-        return result - imageState.getDestroyedEntriesCount();
+        int destroyedEntriesCount = imageState.getDestroyedEntriesCount();
+        if (result < destroyedEntriesCount) {
+          logger.error("Incorrect region size: mapSize={}, destroyedEntriesCount={}.", result,
+              destroyedEntriesCount);
+        }
+        return result - destroyedEntriesCount;
+      }
+
+      int tombstoneNumber = tombstoneCount.get();
+      if (result < tombstoneNumber) {
+        logger.error("Incorrect region size: mapSize={}, tombstoneCount={}.", result,
+            tombstoneNumber);
       }
-      return result - tombstoneCount.get();
+      return result - tombstoneNumber;
     }
   }