Add more tests and update comment.

Author: tusharkhandelwal8

firebase-config/src/main/java/com/google/firebase/remoteconfig/internal/ConfigAutoFetch.java

@@ -119,7 +119,7 @@ public void listenForNotifications() {
       handleNotifications(inputStream);
     } catch (IOException ex) {
       // If the real-time connection is at an unexpected lifecycle state when the app is
-      // backgrounded, it's expected closing the InputStream will throw an exception.
+      // backgrounded, it's expected closing the httpURLConnection will throw an exception.
       if (!isInBackground) {
         // Otherwise, the real-time server connection was closed due to a transient issue.
         Log.d(TAG, "Real-time connection was closed due to an exception.", ex);

firebase-config/src/test/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigTest.java

@@ -1566,6 +1566,18 @@ public void realtime_stream_listen_get_inputstream_fail() throws Exception {
     verify(inputStream).close();
   }
 
+  @Test
+  public void realtime_stream_listen_get_inputstream_exception_handling() throws Exception {
+    ConfigAutoFetch configAutoFetchSpy = spy(configAutoFetch);
+    InputStream inputStream = mock(InputStream.class);
+    when(mockHttpURLConnection.getResponseCode()).thenReturn(200);
+    when(mockHttpURLConnection.getInputStream()).thenThrow(IOException.class);
+    configAutoFetchSpy.listenForNotifications();
+
+    verify(mockHttpURLConnection, times(1)).getInputStream();
+    verify(inputStream, never()).close();
+  }
+
   @Test
   public void realtime_stream_autofetch_success() throws Exception {
     // Setup activated configs with keys "string_param", "long_param"