use mutitenant buffer cache for inverted index tests
diff --git a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
index afeaf90..5f9f87c 100644
--- a/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
+++ b/hyracks/hyracks-storage-am-lsm-invertedindex/src/main/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/ondisk/OnDiskInvertedIndex.java
@@ -161,7 +161,7 @@
     @Override
     public synchronized void activate() throws HyracksDataException {
         if (isOpen) {
-            return;
+            throw new HyracksDataException("Failed to activate the index since it is already activated.");
         }
 
         btree.activate();
@@ -190,7 +190,7 @@
     @Override
     public synchronized void deactivate() throws HyracksDataException {
         if (!isOpen) {
-            return;
+            throw new HyracksDataException("Failed to deactivate the index since it is already deactivated.");
         }
 
         btree.deactivate();
diff --git a/hyracks/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/common/LSMInvertedIndexTestHarness.java b/hyracks/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/common/LSMInvertedIndexTestHarness.java
index 9edeeed..e1f6232 100644
--- a/hyracks/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/common/LSMInvertedIndexTestHarness.java
+++ b/hyracks/hyracks-tests/hyracks-storage-am-lsm-invertedindex-test/src/test/java/edu/uci/ics/hyracks/storage/am/lsm/invertedindex/common/LSMInvertedIndexTestHarness.java
@@ -35,6 +35,7 @@
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.ILSMOperationTracker;
 import edu.uci.ics.hyracks.storage.am.lsm.common.api.IVirtualBufferCache;
 import edu.uci.ics.hyracks.storage.am.lsm.common.freepage.VirtualFreePageManager;
+import edu.uci.ics.hyracks.storage.am.lsm.common.impls.MultitenantVirtualBufferCache;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.NoMergePolicy;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.NoOpIOOperationCallback;
 import edu.uci.ics.hyracks.storage.am.lsm.common.impls.SynchronousScheduler;
@@ -112,7 +113,9 @@
         TestStorageManagerComponentHolder.init(diskPageSize, diskNumPages, diskMaxOpenFiles);
         diskBufferCache = TestStorageManagerComponentHolder.getBufferCache(ctx);
         diskFileMapProvider = TestStorageManagerComponentHolder.getFileMapProvider(ctx);
-        virtualBufferCache = new VirtualBufferCache(new HeapBufferAllocator(), memPageSize, memNumPages);
+        virtualBufferCache = new MultitenantVirtualBufferCache(new VirtualBufferCache(new HeapBufferAllocator(),
+                memPageSize, memNumPages));
+        virtualBufferCache.open();
         virtualFreePageManager = new VirtualFreePageManager(memNumPages);
         ioManager = TestStorageManagerComponentHolder.getIOManager();
         ioDeviceId = 0;
@@ -138,6 +141,7 @@
             }
             dir.delete();
         }
+        virtualBufferCache.close();
     }
 
     public FileReference getInvListsFileRef() {