improve completions in closures and switch statements

pkg/analysis_server/test/services/completion/dart/optype_test.dart

Index: pkg/analysis_server/test/services/completion/dart/optype_test.dart
diff --git a/pkg/analysis_server/test/services/completion/dart/optype_test.dart b/pkg/analysis_server/test/services/completion/dart/optype_test.dart
index 9a6982b63fa48dc5b571d294627c6e8ef0907d61..eeada57727ebe8d0deaacd4067682c9a6cd67c4a 100644
--- a/pkg/analysis_server/test/services/completion/dart/optype_test.dart
+++ b/pkg/analysis_server/test/services/completion/dart/optype_test.dart
@@ -142,6 +142,16 @@ class OpTypeTest {
     assertOpType(typeNames: true);
   }
 
+  test_AsIdentifier() {
+    addTestSource('class A {var asdf; foo() {as^}');
+    assertOpType(returnValue: true, typeNames: true, voidReturn: true);
+  }
+
+  test_AsIdentifier2() {
+    addTestSource('class A {var asdf; foo() {A as^}');
+    assertOpType();
+  }
+
   test_Assert() {
     addTestSource('main() {assert(^)}');
     assertOpType(returnValue: true, typeNames: true);
@@ -1359,6 +1369,11 @@ class C2 {
     assertOpType(returnValue: true, typeNames: true, voidReturn: true);
   }
 
+  test_SwitchStatement_body_end2() {
+    addTestSource('main() {switch(k) {case 1:as^}}');
+    assertOpType(returnValue: true, typeNames: true, voidReturn: true);
+  }
+
   test_SwitchStatement_expression1() {
     // SimpleIdentifier  SwitchStatement  Block
     addTestSource('main() {switch(^k) {case 1:{}}}');