Revert "RateLimitTest: temporarily dump ConnectivityThread if setUp fails"

This reverts commit cbe17558269328dd08e02228d2766dee02442b6e.

Reason for revert: we found the culprit for the flakiness and b/272147742 is fixed.

Change-Id: I672c42bb57184393588666b6196f3a316f8c99c7
diff --git a/tests/cts/net/src/android/net/cts/RateLimitTest.java b/tests/cts/net/src/android/net/cts/RateLimitTest.java
index 5c93738..36b98fc 100644
--- a/tests/cts/net/src/android/net/cts/RateLimitTest.java
+++ b/tests/cts/net/src/android/net/cts/RateLimitTest.java
@@ -36,7 +36,6 @@
 import android.icu.text.MessageFormat;
 import android.net.ConnectivityManager;
 import android.net.ConnectivitySettingsManager;
-import android.net.ConnectivityThread;
 import android.net.InetAddresses;
 import android.net.IpPrefix;
 import android.net.LinkAddress;
@@ -190,19 +189,7 @@
             // whatever happens, don't leave the device in rate limited state.
             ConnectivitySettingsManager.setIngressRateLimitInBytesPerSecond(mContext, -1);
         }
-        if (mSocket == null) {
-            // HACK(b/272147742): dump ConnectivityThread if test initialization failed.
-            final StackTraceElement[] elements = ConnectivityThread.get().getStackTrace();
-            final StringBuilder sb = new StringBuilder();
-            // Skip first element as it includes the invocation of getStackTrace()
-            for (int i = 1; i < elements.length; i++) {
-                sb.append(elements[i]);
-                sb.append("\n");
-            }
-            Log.e(TAG, sb.toString());
-        } else {
-            mSocket.close();
-        }
+        if (mSocket != null) mSocket.close();
         if (mNetworkAgent != null) mNetworkAgent.unregister();
         if (mTunInterface != null) mTunInterface.getFileDescriptor().close();
         if (mCm != null) mCm.unregisterNetworkCallback(mNetworkCallback);