components: Cleanup class/struct fwd declarations

components/drive/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 COMPONENTS_DRIVE_DRIVE_API_UTIL_H_
 #define COMPONENTS_DRIVE_DRIVE_API_UTIL_H_
 
 #include <memory>
 #include <string>
 
 #include "base/md5.h"
 #include "google_apis/drive/drive_api_error_codes.h"
 #include "google_apis/drive/drive_common_callbacks.h"
 
-class GURL;
-
 namespace base {
 class CancellationFlag;
 class FilePath;
-class Value;
 }  // namespace base
 
-namespace google_apis {
-class ChangeList;
-class ChangeResource;
-class FileList;
-class FileResource;
-class ResourceEntry;
-}  // namespace google_apis
-
 namespace drive {
 namespace util {
 
 // Google Apps MIME types:
 const char kGoogleDocumentMimeType[] = "application/vnd.google-apps.document";
 const char kGoogleDrawingMimeType[] = "application/vnd.google-apps.drawing";
 const char kGooglePresentationMimeType[] =
     "application/vnd.google-apps.presentation";
 const char kGoogleSpreadsheetMimeType[] =
     "application/vnd.google-apps.spreadsheet";
@@ skipping 36 matching lines @@
 bool IsKnownHostedDocumentMimeType(const std::string& mime_type);
 
 // Returns true if the given file path has an extension corresponding to one of
 // hosted document types.
 bool HasHostedDocumentExtension(const base::FilePath& path);
 
 }  // namespace util
 }  // namespace drive
 
 #endif  // COMPONENTS_DRIVE_DRIVE_API_UTIL_H_