Fix examples which uses typo function.

chrome/common/extensions/docs/templates/intros/input_ime.html

 <h2 id="manifest">Manifest</h2>
 <p>You must declare the "input" permission
 in the <a href="manifest.html">extension manifest</a>
 to use the input.ime API.
 For example:</p>
 <pre>{
   "name": "My extension",
   ...
   <b>"permissions": [
     "input"
   ]</b>,
   ...
 }</pre>
 
 <h2 id="overview-examples">Examples</h2>
 
 <p>
 The following code creates an IME that converts typed letters to upper case.
 </p>
 
 <pre>
 var context_id = -1;
 
 chrome.input.ime.onFocus.addListener(function(context) {
   context_id = context.contextID;
 });
 
-chrome.input.ime.onKeyEventAsync.addListener(
+chrome.input.ime.onKeyEvent.addListener(
   function(engineID, keyData) {
     if (keyData.type == "keydown" && keyData.key.match(/^[a-z]$/)) {
       chrome.input.ime.commitText({"contextID": context_id,
                                    "text": keyData.key.toUpperCase()});
       return true;
     } else {
       return false;
     }
   });
 </pre>
 
 <p>
 For an example of using this API, see the
 <a
   href="http://src.chromium.org/viewvc/chrome/trunk/src/chrome/common/extensions/docs/examples/api/input.ime/basic/">basic input.ime sample</a>.
 For other examples and for help in viewing the source code, see
 <a href="samples.html">Samples</a>.
 </p>