base: Remove the string logging from CHECK().

components/sync/engine_impl/loopback_server/loopback_server.cc

Index: components/sync/engine_impl/loopback_server/loopback_server.cc
diff --git a/components/sync/engine_impl/loopback_server/loopback_server.cc b/components/sync/engine_impl/loopback_server/loopback_server.cc
index 88eb7ca095bbca0a13f7be92539401af5f6ad69f..da2163fe93add24231ee865fbab74ab7de5f0466 100644
--- a/components/sync/engine_impl/loopback_server/loopback_server.cc
+++ b/components/sync/engine_impl/loopback_server/loopback_server.cc
@@ -123,8 +123,8 @@ class UpdateSieve {
 
 std::unique_ptr<UpdateSieve> UpdateSieve::Create(
     const sync_pb::GetUpdatesMessage& get_updates_message) {
-  CHECK_GT(get_updates_message.from_progress_marker_size(), 0)
-      << "A GetUpdates request must have at least one progress marker.";
+  // A GetUpdates request must have at least one progress marker.
+  CHECK_GT(get_updates_message.from_progress_marker_size(), 0);
 
   UpdateSieve::ModelTypeToVersionMap request_from_version;
   int64_t min_version = std::numeric_limits<int64_t>::max();
@@ -137,7 +137,8 @@ std::unique_ptr<UpdateSieve> UpdateSieve::Create(
     // first request for this type).
     if (marker.has_token() && !marker.token().empty()) {
       bool parsed = base::StringToInt64(marker.token(), &version);
-      CHECK(parsed) << "Unable to parse progress marker token.";
+      // Unable to parse progress marker token.
+      CHECK(parsed);
     }
     ModelType model_type =
         syncer::GetModelTypeFromSpecificsFieldNumber(marker.data_type_id());
@@ -237,7 +238,8 @@ void LoopbackServer::HandleCommand(
 
   sync_pb::ClientToServerMessage message;
   bool parsed = message.ParseFromString(request);
-  CHECK(parsed) << "Unable to parse the ClientToServerMessage.";
+  // Unable to parse the ClientToServerMessage.
+  CHECK(parsed);
 
   sync_pb::ClientToServerResponse response_proto;