Add viewer for pdf files (#1843)

Adds an viewer for pdf files to the source code browser.

scm-ui/ui-components/src/PdfViewer.stories.tsx

@@ -0,0 +1,34 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020-present Cloudogu GmbH and Contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+import React from "react";
+import PdfViewer from "./PdfViewer";
+// @ts-ignore no need to declare module for a single import
+import pdf from "./__resources__/doc.pdf";
+import { storiesOf } from "@storybook/react";
+
+storiesOf("PdfViewer", module)
+  .add("Simple", () => <PdfViewer src={pdf} />)
+  .add("Error", () => <PdfViewer src="/does/not/exists" />)
+  .add("Error with download URL", () => <PdfViewer src="/does/not/exists" download={pdf} />);