Adds an API for inserting fake devices to internals

third_party/WebKit/Source/modules/mediastream/testing/InternalsMediaStream.cpp

Index: third_party/WebKit/Source/modules/mediastream/testing/InternalsMediaStream.cpp
diff --git a/third_party/WebKit/Source/modules/mediastream/testing/InternalsMediaStream.cpp b/third_party/WebKit/Source/modules/mediastream/testing/InternalsMediaStream.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..e94de2602ed17ab2898b4d3b75718a7d67b1f250
--- /dev/null
+++ b/third_party/WebKit/Source/modules/mediastream/testing/InternalsMediaStream.cpp
@@ -0,0 +1,24 @@
+// Copyright 2017 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 "modules/mediastream/testing/InternalsMediaStream.h"
+
+#include "bindings/core/v8/ScriptPromise.h"
+#include "bindings/core/v8/ScriptPromiseResolver.h"
+
+namespace blink {
+
+ScriptPromise InternalsMediaStream::addFakeDevice(
+    ScriptState* scriptState,
+    Internals&,
+    const MediaDeviceInfo* deviceInfo,
+    const MediaTrackConstraints& capabilities,
+    const MediaStreamTrack* dataSource) {
+  ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
+  ScriptPromise promise = resolver->promise();
+  resolver->reject();
+  return promise;
+}
+
+}  // namespace blink