Add network tester client [android] to be able to test mobile networks in terms of packet size and sending rates.

BUG=webrtc:7426

Review-Url: https://codereview.webrtc.org/2787863002
Cr-Commit-Position: refs/heads/master@{#17789}
diff --git a/webrtc/tools/network_tester/jni.cpp b/webrtc/tools/network_tester/jni.cpp
new file mode 100644
index 0000000..469a1c9
--- /dev/null
+++ b/webrtc/tools/network_tester/jni.cpp
@@ -0,0 +1,63 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <jni.h>
+#undef JNIEXPORT
+#define JNIEXPORT __attribute__((visibility("default")))
+#include <string>
+
+#include "webrtc/tools/network_tester/test_controller.h"
+
+extern "C" JNIEXPORT jlong JNICALL
+Java_com_google_media_networktester_NetworkTester_CreateTestController(
+    JNIEnv* jni,
+    jclass) {
+  return reinterpret_cast<intptr_t>(new webrtc::TestController(
+      0, 0, "/mnt/sdcard/network_tester_client_config.dat",
+      "/mnt/sdcard/network_tester_client_packet_log.dat"));
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_media_networktester_NetworkTester_TestControllerConnect(
+    JNIEnv* jni,
+    jclass,
+    jlong native_pointer) {
+  reinterpret_cast<webrtc::TestController*>(native_pointer)
+      ->SendConnectTo("85.195.237.107", 9090);
+}
+
+extern "C" JNIEXPORT bool JNICALL
+Java_com_google_media_networktester_NetworkTester_TestControllerIsDone(
+    JNIEnv* jni,
+    jclass,
+    jlong native_pointer) {
+  return reinterpret_cast<webrtc::TestController*>(native_pointer)
+      ->IsTestDone();
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_media_networktester_NetworkTester_TestControllerRun(
+    JNIEnv* jni,
+    jclass,
+    jlong native_pointer) {
+  reinterpret_cast<webrtc::TestController*>(native_pointer)->Run();
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_com_google_media_networktester_NetworkTester_DestroyTestController(
+    JNIEnv* jni,
+    jclass,
+    jlong native_pointer) {
+  webrtc::TestController* test_controller =
+      reinterpret_cast<webrtc::TestController*>(native_pointer);
+  if (test_controller) {
+    delete test_controller;
+  }
+}