QuickView: Improve security by rendering images inside webview.

ui/file_manager/file_manager/foreground/elements/files_safe_img.html

Index: ui/file_manager/file_manager/foreground/elements/files_safe_img.html
diff --git a/ui/file_manager/file_manager/foreground/elements/files_safe_img.html b/ui/file_manager/file_manager/foreground/elements/files_safe_img.html
new file mode 100644
index 0000000000000000000000000000000000000000..1eaf84a43ddcfd995a808373777a7d40f4c7962e
--- /dev/null
+++ b/ui/file_manager/file_manager/foreground/elements/files_safe_img.html
@@ -0,0 +1,23 @@
+<!-- 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.
+-->
+
+<dom-module id="files-safe-img">
+  <style>
+    #content {
+      height: 100%;
+      width: 100%;
+    }
+    webview {
+      display: inline-block;
+      height: 100%;
+      width: 100%;
+    }
+  </style>
+  <template>
+    <div id="content"></div>
+  </template>
+</dom-module>
+
+<script src="files_safe_img.js"></script>