Add hideKeyboard API to chrome.experimental.input.

chrome/browser/resources/keyboard/main.js

 // Copyright (c) 2011 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 simple, English virtual keyboard implementation.
  */
 
 var KEY_MODE = 'key';
 var SHIFT_MODE = 'shift';
@@ skipping 395 matching lines @@
     this.modeElements_[mode] = document.createElement('div');
     this.modeElements_[mode].className = 'key';
 
     var hide = document.createElement('div');
     hide.className = 'image-key hide';
     this.modeElements_[mode].appendChild(hide);
 
     this.sizeElement(mode, height);
 
     this.modeElements_[mode].onclick = function() {
-      // TODO(bryeung): need a way to cancel the keyboard
+      chrome.experimental.input.hideKeyboard();
     };
 
     return this.modeElements_[mode];
   }
 };
 
 /**
  * A container for keys.
  * @param {number} position The position of the row (0-3).
  * @param {Array.<BaseKey>} keys The keys in the row.
@@ skipping 251 matching lines @@
   for (var i = 0; i < allRows.length; ++i) {
     body.appendChild(allRows[i].makeDOM(getRowHeight()));
     allRows[i].showMode(KEY_MODE);
   }
 
   window.onresize();
 }
 
 // TODO(bryeung): would be nice to leave less gutter (without causing
 // rendering issues with floated divs wrapping at some sizes).