Add SetImageData api to chrome.clipboard.

chrome/test/data/extensions/api_test/clipboard/set_image_data/main.js

Index: chrome/test/data/extensions/api_test/clipboard/set_image_data/main.js
diff --git a/chrome/test/data/extensions/api_test/clipboard/set_image_data/main.js b/chrome/test/data/extensions/api_test/clipboard/set_image_data/main.js
new file mode 100644
index 0000000000000000000000000000000000000000..747d5b856c395b8e8b9604005ea9c5d720ec0323
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/clipboard/set_image_data/main.js
@@ -0,0 +1,21 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.

[Devlin, 2016/12/09 15:23:48]

no (c) (all files)

[jennyz, 2016/12/14 01:15:36]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var clipDataChangedCount = 0;
+
+chrome.app.runtime.onLaunched.addListener(function(launchData) {
+  console.log('onLaunched');

[Devlin, 2016/12/09 15:23:49]

remove debugging logs

[jennyz, 2016/12/14 01:15:36]

Done.

+  chrome.app.window.create('app_main.html',
+      { 'width': 500,
+        'height': 500 },

[Devlin, 2016/12/09 15:23:50]

Please follow JS style here.  Also, if you don't do anything with the callback,
don't pass one,.

So, something like:
chrome.app.window.create('app_main.html', {width: 500, height: 500});

[jennyz, 2016/12/14 01:15:36]

Done.

+      function(window) {
+  });
+});
+
+chrome.clipboard.onClipboardDataChanged.addListener(function() {
+  clipDataChangedCount++;
+  console.log('onClipboardDataChanged ' + clipDataChangedCount);
+  chrome.test.sendMessage("clipboard data changed " + clipDataChangedCount);
+});
+