Set up initial MockURLRequestJob tests for Cronet

components/cronet/android/test/mock_url_request_job.cc

Index: components/cronet/android/test/mock_url_request_job.cc
diff --git a/components/cronet/android/test/mock_url_request_job.cc b/components/cronet/android/test/mock_url_request_job.cc
new file mode 100644
index 0000000000000000000000000000000000000000..923b89bb14eb27cddcce4556e745163465570729
--- /dev/null
+++ b/components/cronet/android/test/mock_url_request_job.cc
@@ -0,0 +1,42 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/android/jni_android.h"
+#include "base/android/jni_registrar.h"
+#include "base/android/jni_string.h"
+#include "base/macros.h"
+#include "jni/URLRequestJobUtil_jni.h"
+#include "net/base/net_errors.h"
+#include "net/test/url_request_failed_job.h"
+#include "net/url_request/url_request_filter.h"
+#include "url/gurl.h"
+
+using base::android::ConvertJavaStringToUTF8;
+
+namespace cronet {
+namespace {
+// Fails requests using ERR_CONNECTION_RESET.
+net::URLRequestJob* FailedJobFactory(
+    net::URLRequest* request,
+    net::NetworkDelegate* network_delegate,
+    const std::string& scheme) {
+  return new net::URLRequestFailedJob(
+      request, network_delegate, net::ERR_CONNECTION_RESET);
+}
+
+}  // namespace
+
+static void FailURLRequestJob(JNIEnv* env, jclass jcaller, jstring jurl) {
+  net::URLRequestFilter* filter = net::URLRequestFilter::GetInstance();
+  filter->AddUrlHandler(
+      GURL(ConvertJavaStringToUTF8(env, jurl)), &FailedJobFactory);

[mmenke, 2014/09/03 18:02:35]

Suggest just using URLRequestFailedJob::AddUrlHandler(), and always invoking it
on test startup - can actually move the call into JNI_OnLoad in
cronet_tests_jni, and you won't even need any new JNI calls, just the extra
initialization line.

Then your test can just navigate to, say, "http://mock.failed.request/101", and
requests for that URL will fail with ERR_CONNECTION_RESET (That's error 101. 
See net/base/net_error_list.h for a list of error codes, though not sure we
currently really care about which code a request fails with).

+}
+
+// Explicitly register static JNI functions.
+bool MockURLRequestJobRegisterJni(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+}  // namespace cronet
+