[Chromoting] Let the webapp detect new clipboard text items when it gets focus.

remoting/webapp/clipboard.js

Index: remoting/webapp/clipboard.js
diff --git a/remoting/webapp/clipboard.js b/remoting/webapp/clipboard.js
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index 0000000000000000000000000000000000000000..f16e19ee742e808523375fde96084981ac7818c6
--- /dev/null
+++ b/remoting/webapp/clipboard.js
@@ -0,0 +1,54 @@
+// Copyright (c) 2012 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.
+
+/**
+ * @fileoverview
+ * A class for moving clipboard items between the plugin and the OS.
+ */
+
+'use strict';
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+/**
+ * @constructor
+ */
+remoting.Clipboard = function() {
+};
+
+/** @type {string} */
+remoting.Clipboard.prototype.recentItemText = "";
+
+/**
+ * Accepts a clipboard from the OS, and sends any changed clipboard items to
+ * the host.
+ *
+ * Currently only text items are supported.
+ *
+ * @param {remoting.ClipboardData} clipboardData
+ * @return {void} Nothing.
+ */
+remoting.Clipboard.prototype.toHost = function(clipboardData) {
+  if (!clipboardData || !clipboardData.types || !clipboardData.getData) {
+    return;
+  }
+  var textType = 'text/plain';

[Jamie, 2012/03/14 00:43:47]

Since this is a constant, I'd be inclined to move it out of the function and
call it TEXT_TYPE. You could even make it a single-element enum to make it clear
how it would be extended.

+  for (var i = 0; i < clipboardData.types.length; i++) {
+    var type = clipboardData.types[i];
+    if (type == textType) {
+      var item = clipboardData.getData(type);
+      if (!item) {
+        item = "";
+      }
+      if (item != this.recentItemText) {
+        // TODO(simonmorris): Pass the clipboard text item to the plugin.
+        this.recentItemText = item;
+      }
+    }
+  }
+};
+
+/** @type {remoting.Clipboard} */
+remoting.clipboard = null;