Add MediaError.message

third_party/WebKit/Source/core/html/media/MediaError.cpp

+// 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 "core/html/media/MediaError.h"
+
+#include "platform/json/JSONValues.h"
+
+namespace blink {
+
+MediaError::MediaError(ErrorCode code, const JSONObject* messages)
+    : code_(code) {
+  if (!messages->size()) {
+    // A message containing an empty serialized JSON object ("{}") is invalid
+    // and just an empty string should be used in this case per spec:
+    // https://html.spec.whatwg.org/multipage/embedded-content.html#mediaerror
+    // "...whose message is a string containing any details the user agent is
+    // able to supply about the cause of the error condition, or the empty
+    // string if the user agent is unable to supply such details..."
+    message_ = "";
+    return;
+  }
+
+  // https://html.spec.whatwg.org/multipage/embedded-content.html#mediaerror
+  // "The message and message format are not generally uniform across
+  // different user agents."
+  // We use a readily-parsable serialized JSON object to represent these error
+  // messages, if we have anything additional to report beyond just the code.
+  message_ = messages->ToJSONString();
+}
+
+}  // namespace blink