Add SNAPSHOT sync mode to LocalFileSyncContext::PrepareForSync

chrome/browser/sync_file_system/local/local_file_sync_service.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/sync_file_system/local/local_file_sync_service.h"
 
 #include "base/stl_util.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 218 matching lines @@
                    AsWeakPtr(),
                    url,
                    file_system_context,
                    callback));
     return;
   }
 
   DCHECK(ContainsKey(origin_to_contexts_, url.origin()));
   sync_context_->PrepareForSync(
       origin_to_contexts_[url.origin()], url,
+      LocalFileSyncContext::SYNC_EXCLUSIVE,
       base::Bind(&PrepareForProcessRemoteChangeCallbackAdapter, callback));
 }
 
 void LocalFileSyncService::ApplyRemoteChange(
     const FileChange& change,
     const base::FilePath& local_path,
     const FileSystemURL& url,
     const SyncStatusCallback& callback) {
   DCHECK(ContainsKey(origin_to_contexts_, url.origin()));
   sync_context_->ApplyRemoteChange(
@@ skipping 162 matching lines @@
   }
 
   if (status == SYNC_FILE_ERROR_NOT_FOUND &&
       processed_change.change() == FileChange::FILE_CHANGE_DELETE) {
     // This must be ok (and could happen).
     status = SYNC_STATUS_OK;
   }
 
   const FileSystemURL& url = sync_file_info.url;
   if (status != SYNC_STATUS_OK || changes.empty()) {
-    if (status == SYNC_STATUS_OK || status == SYNC_STATUS_HAS_CONFLICT) {
-      // Clear the recorded changes for the URL if the sync was successfull
-      // OR has failed due to conflict (so that we won't stick to the same
-      // conflicting file again and again).
-      DCHECK(ContainsKey(origin_to_contexts_, url.origin()));
-      sync_context_->ClearChangesForURL(
-          origin_to_contexts_[url.origin()], url,
-          base::Bind(&LocalFileSyncService::RunLocalSyncCallback,
-                     AsWeakPtr(), status, url));
-      return;
-    }
-    RunLocalSyncCallback(status, url);
+    DCHECK(ContainsKey(origin_to_contexts_, url.origin()));
+    sync_context_->CommitChangeStatusForURL(
+        origin_to_contexts_[url.origin()], url, status,
+        base::Bind(&LocalFileSyncService::RunLocalSyncCallback,
+                  AsWeakPtr(), status, url));
     return;
   }
 
   FileChange next_change = changes.front();
   local_change_processor_->ApplyLocalChange(
       changes.front(),
       sync_file_info.local_file_path,
       sync_file_info.metadata,
       url,
       base::Bind(&LocalFileSyncService::ProcessNextChangeForURL,
                  AsWeakPtr(), sync_file_info,
                  next_change, changes.PopAndGetNewList()));
 }
 
 }  // namespace sync_file_system