Implement query translation from GData WAPI to Drive API v2.

chrome/browser/google_apis/drive_api_util.h

 // 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.
 
 #ifndef CHROME_BROWSER_GOOGLE_APIS_DRIVE_API_UTIL_H_
 #define CHROME_BROWSER_GOOGLE_APIS_DRIVE_API_UTIL_H_
 
 #include <string>
 
 namespace google_apis {
 namespace util {
 
 // Returns true if Drive v2 API is enabled via commandline switch.
 bool IsDriveV2ApiEnabled();
 
 }  // namespace util
 
 namespace drive {
 namespace util {
 
 // Escapes ' to \' in the |str|. This is designed to use for string value of
 // search parameter on Drive API v2.
 // See also: https://developers.google.com/drive/search-parameters
 std::string EscapeQueryStringValue(const std::string& str);
 
+// Parses the query, and builds a search query for Drive API v2.
+// This only supports:
+//   Regular query (e.g. dog => fullText contains 'dog')
+//   Conjunctions
+//     (e.g. dog cat => fullText contains 'dog' and fullText contains 'cat')
+//   Exclusion query (e.g. -cat => not fullText contains 'cat').
+//   Quoted query (e.g. "dog cat" => fullText contains 'dog cat').
+// See also: https://developers.google.com/drive/search-parameters
+std::string TranslateQuery(const std::string& original_query);
+
 }  // namespace util
 }  // namespace drive
 }  // namespace google_apis
 
 #endif  // CHROME_BROWSER_GOOGLE_APIS_DRIVE_API_UTIL_H_