Fix delete of stack allocated object causing test crashes.

Introduced in r8264.

BUG=4173
R=bjornv@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/37959004

Cr-Commit-Position: refs/heads/master@{#8266}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8266 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.cc b/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.cc
index b2627a1..8702e3a 100644
--- a/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.cc
+++ b/webrtc/modules/remote_bitrate_estimator/test/bwe_test_framework.cc
@@ -805,10 +805,8 @@
       return new RembSendSideBwe(kbps, observer, clock);
     case kFullSendSideEstimator:
       return new FullSendSideBwe(kbps, observer, clock);
-    case kNullEstimator: {
-      static NullSendSideBwe null_bwe;
-      return &null_bwe;
-    }
+    case kNullEstimator:
+      return new NullSendSideBwe();
   }
   assert(false);
   return NULL;