Move exception support to its own library

pkg/analysis_server/lib/src/protocol_server.dart

Index: pkg/analysis_server/lib/src/protocol_server.dart
diff --git a/pkg/analysis_server/lib/src/protocol_server.dart b/pkg/analysis_server/lib/src/protocol_server.dart
index 864f04fbf727641a2570214b840bb6c8766ba54e..0a00a174501c47c616efdb703ae646a5856be115 100644
--- a/pkg/analysis_server/lib/src/protocol_server.dart
+++ b/pkg/analysis_server/lib/src/protocol_server.dart
@@ -13,11 +13,11 @@ import 'package:analyzer/dart/ast/ast.dart' as engine;
 import 'package:analyzer/dart/ast/visitor.dart' as engine;
 import 'package:analyzer/dart/element/element.dart' as engine;
 import 'package:analyzer/dart/element/type.dart' as engine;
+import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/source/error_processor.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart' as engine;
 import 'package:analyzer/src/generated/engine.dart' as engine;
 import 'package:analyzer/src/generated/error.dart' as engine;
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart' as engine;
 import 'package:analyzer/src/generated/utilities_dart.dart' as engine;