Implement clipboardRead/Write content capabilities

chrome/test/data/extensions/content_capabilities/capability_tests.js

Index: chrome/test/data/extensions/content_capabilities/capability_tests.js
diff --git a/chrome/test/data/extensions/content_capabilities/capability_tests.js b/chrome/test/data/extensions/content_capabilities/capability_tests.js
new file mode 100644
index 0000000000000000000000000000000000000000..65eb20ee903e25099702773f6130e4c65e330717
--- /dev/null
+++ b/chrome/test/data/extensions/content_capabilities/capability_tests.js
@@ -0,0 +1,17 @@
+// Copyright 2014 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.
+
+(function() {
+
+window.tests = {
+  canReadClipboard: function() {
+    domAutomationController.send(document.execCommand('paste'));
+  },
+
+  canWriteClipboard: function() {
+    domAutomationController.send(document.execCommand('copy'));
+  },
+};
+
+}());