Sync FakeServer cleanup: CHECKs and logging info

sync/test/fake_server/fake_server.cc

 // 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.
 
 #include "sync/test/fake_server/fake_server.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 #include <vector>
@@ skipping 97 matching lines @@
 
   // Maps data type IDs to the latest version seen for that type.
   const ModelTypeToVersionMap request_from_version_;
 
   // The minimum version seen among all data types.
   const int min_version_;
 };
 
 scoped_ptr<UpdateSieve> UpdateSieve::Create(
     const sync_pb::GetUpdatesMessage& get_updates_message) {
-  DCHECK_GT(get_updates_message.from_progress_marker_size(), 0);
+  CHECK_GT(get_updates_message.from_progress_marker_size(), 0)
+      << "A GetUpdates request must have at least one progress marker.";
 
   UpdateSieve::ModelTypeToVersionMap request_from_version;
   int64 min_version = std::numeric_limits<int64>::max();
   for (int i = 0; i < get_updates_message.from_progress_marker_size(); i++) {
     sync_pb::DataTypeProgressMarker marker =
         get_updates_message.from_progress_marker(i);
 
     int64 version = 0;
     // Let the version remain zero if there is no token or an empty token (the
     // first request for this type).
     if (marker.has_token() && !marker.token().empty()) {
       bool parsed = base::StringToInt64(marker.token(), &version);
-      DCHECK(parsed);
+      CHECK(parsed) << "Unable to parse progress marker token.";
     }
 
     ModelType model_type = syncer::GetModelTypeFromSpecificsFieldNumber(
         marker.data_type_id());
     request_from_version[model_type] = version;
 
     if (version < min_version)
       min_version = version;
   }
 
@@ skipping 74 matching lines @@
 
 void FakeServer::HandleCommand(const string& request,
                                const HandleCommandCallback& callback) {
   if (!authenticated_) {
     callback.Run(0, net::HTTP_UNAUTHORIZED, string());
     return;
   }
 
   sync_pb::ClientToServerMessage message;
   bool parsed = message.ParseFromString(request);
-  DCHECK(parsed);
+  CHECK(parsed) << "Unable to parse the ClientToServerMessage.";
 
   sync_pb::SyncEnums_ErrorType error_code;
   sync_pb::ClientToServerResponse response_proto;
 
   if (message.has_store_birthday() &&
       message.store_birthday() != store_birthday_) {
     error_code = sync_pb::SyncEnums::NOT_MY_BIRTHDAY;
   } else {
     bool success = false;
     switch (message.message_contents()) {
@@ skipping 270 matching lines @@
 
 void FakeServer::AddObserver(Observer* observer) {
   observers_.AddObserver(observer);
 }
 
 void FakeServer::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
 }  // namespace fake_server