GN(Android): Fix CleanupReferenceTest#testCreateMany failing.

content/public/android/javatests/src/org/chromium/content/common/CleanupReferenceTest.java

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.content.common;
 
 import android.test.InstrumentationTestCase;
 import android.test.suitebuilder.annotation.SmallTest;
 
 import org.chromium.base.annotations.SuppressFBWarnings;
@@ skipping 73 matching lines @@
         ReferredObject[] instances = new ReferredObject[instanceCount];
 
         for (int i = 0; i < instanceCount; ++i) {
             instances[i] = new ReferredObject();
             assertEquals(i + 1, sObjectCount.get());
         }
 
         instances = null;
         // Ensure compiler / instrumentation does not strip out the assignment.
         assertTrue(instances == null);
+        // Calling sObjectCount.get() before collectGarbage() seems to be required for the objects
+        // to be GC'ed only when building using GN.
+        assertTrue(sObjectCount.get() != -1);
         collectGarbage();
         assertTrue(CriteriaHelper.pollForCriteria(new Criteria() {
             @Override
             public boolean isSatisfied() {
                 return sObjectCount.get() == 0;
             }
         }));
     }
 
 }