Add srcObject attribute of type MediaStream to HTMLMediaElement.

third_party/WebKit/Source/modules/srcobject/HTMLMediaElementSrcObject.cpp

+// Copyright 2016 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/srcobject/HTMLMediaElementSrcObject.h"
+
+#include "modules/mediastream/MediaStream.h"
+#include "modules/mediastream/URLMediaStream.h"
+#include "wtf/Assertions.h"
+
+namespace blink {
+
+HTMLMediaElementSrcObject::HTMLMediaElementSrcObject()
+    : m_srcObject(nullptr)
+{
+}
+
+// static
+MediaStream* HTMLMediaElementSrcObject::srcObject(HTMLMediaElement& element)
+{
+    HTMLMediaElementSrcObject& thisElement = HTMLMediaElementSrcObject::from(element);
+    return thisElement.m_srcObject;
+}
+
+// static
+void HTMLMediaElementSrcObject::setSrcObject(HTMLMediaElement& element, MediaStream* mediaStream)
+{
+    HTMLMediaElementSrcObject& thisElement = HTMLMediaElementSrcObject::from(element);
+    thisElement.m_srcObject = mediaStream;
+    if (!mediaStream) {
+        element.setSrcObject(WebMediaElementSource());
+        return;
+    }
+    WebMediaStream webStream = WebMediaStream(mediaStream->descriptor());
+    WebMediaElementSource webSource(webStream);
+    element.setSrcObject(webSource);
+}
+
+HTMLMediaElementSrcObject& HTMLMediaElementSrcObject::from(HTMLMediaElement& element)
+{
+    HTMLMediaElementSrcObject* supplement = static_cast<HTMLMediaElementSrcObject*>(WillBeHeapSupplement<HTMLMediaElement>::from(element, supplementName()));
+    if (!supplement) {
+        supplement = new HTMLMediaElementSrcObject();
+        provideTo(element, supplementName(), adoptPtrWillBeNoop(supplement));
+    }
+    return *supplement;
+}
+
+const char* HTMLMediaElementSrcObject::supplementName()
+{
+    return "HTMLMediaElementSrcObject";
+}
+
+DEFINE_TRACE(HTMLMediaElementSrcObject)
+{
+    visitor->trace(m_srcObject);
+    WillBeHeapSupplement<HTMLMediaElement>::trace(visitor);
+}
+
+} // namespace blink