Merge "Avoid waiting unnecessarily if there is no data to return."

tests/cts/hostside/app/src/com/android/cts/net/hostside/AbstractRestrictBackgroundNetworkTestCase.java

@@ -106,6 +106,8 @@ public abstract class AbstractRestrictBackgroundNetworkTestCase {
 
     private static final String KEY_NETWORK_STATE_OBSERVER = TEST_PKG + ".observer";
 
+    private static final String EMPTY_STRING = "";
+
     protected static final int TYPE_COMPONENT_ACTIVTIY = 0;
     protected static final int TYPE_COMPONENT_FOREGROUND_SERVICE = 1;
 
@@ -206,6 +208,8 @@ public abstract class AbstractRestrictBackgroundNetworkTestCase {
                 final String resultData = getResultData();
                 if (resultData == null) {
                     Log.e(TAG, "Received null data from ordered intent");
+                    // Offer an empty string so that the code waiting for the result can return.
+                    result.offer(EMPTY_STRING);
                     return;
                 }
                 result.offer(resultData);