Fix API name in document scan

chrome/common/extensions/api/document_scan.idl

 // 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.
 
-// Use the <code>chrome.document_scan</code> API to discover and retrieve
+// Use the <code>chrome.documentScan</code> API to discover and retrieve
 // images from attached paper document scanners.
 namespace documentScan {
   dictionary ScanOptions {
     // The MIME types that are accepted by the caller.
     DOMString[]? mimeTypes;
 
     // The number of scanned images allowed (defaults to 1).
     long? maxImages;
   };
 
@@ skipping 12 matching lines @@
   callback ScanCallback = void (ScanResults result);
 
   interface Functions {
     // Performs a document scan.  On success, the PNG data will be
     // sent to the callback.
     // |options| : Object containing scan parameters.
     // |callback| : Called with the result and data from the scan.
     static void scan(ScanOptions options, ScanCallback callback);
   };
 };