Fix CronetUrlRequestTest#testFailures flake

components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java

Index: components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java
diff --git a/components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java b/components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java
index da46d1b9c1858b3f569c2a4d846388181ece8dc3..ee6a7f11bbcf4f948d4a1ae85b29e4559a057073 100644
--- a/components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java
+++ b/components/cronet/android/test/javatests/src/org/chromium/net/TestUrlRequestCallback.java
@@ -231,7 +231,6 @@ class TestUrlRequestCallback extends UrlRequest.Callback {
         mOnErrorCalled = true;
         mError = error;
         openDone();
-        maybeThrowCancelOrPause(request);

[kapishnikov, 2016/08/30 16:15:57]

Why don't we update mResponseStep to ON_FAILED here? This would allow us to
potentially test the listener exceptions and cancelations that can happen in
onFailed() callback.

[xunjieli, 2016/08/30 17:05:43]

There is no enum ON_FAILED. We can certainly add one, but I don't think it's a
good idea to call maybeThrowCancelOrPause() with openDone().  If we want to test
failure or cancellation during onFailed, we need to do something with
openDone(). Otherwise, it's a bit confusing that the request is "done", but we
are still "canceling it or throwing an exception". WDYT?

     }
 
     @Override