Fix incremental scanner's computation of scanEnd.

pkg/analyzer/test/generated/parser_test.dart

Index: pkg/analyzer/test/generated/parser_test.dart
diff --git a/pkg/analyzer/test/generated/parser_test.dart b/pkg/analyzer/test/generated/parser_test.dart
index 7ee8a2c21c7a2b2fa633f0944227f5601461722b..66a62134eabf169507a67425f35aa62560e56a33 100644
--- a/pkg/analyzer/test/generated/parser_test.dart
+++ b/pkg/analyzer/test/generated/parser_test.dart
@@ -2690,6 +2690,23 @@ class IncrementalParserTest extends EngineTestCase {
         "; }");
   }
 
+  void test_insert_statement_in_method_with_mismatched_braces() {
+    _assertParse('''
+class C {
+  void f() {
+''', '', 'g();', '''
+    if (b) {
+
+
+  }
+
+  void g() {
+    h((x) {});
+  }
+}
+''');
+  }
+
   void test_insert_whitespace_end() {
     // "f() => a + b;"
     // "f() => a + b; "