Issue 5621. Report error when { is missing in 'switch'

compiler/java/com/google/dart/compiler/parser/DartParser.java

Index: compiler/java/com/google/dart/compiler/parser/DartParser.java
diff --git a/compiler/java/com/google/dart/compiler/parser/DartParser.java b/compiler/java/com/google/dart/compiler/parser/DartParser.java
index c32c0d68884b048b339ff6d6b378e8216d3f495c..c7252457505898501507846fa63cfc8aaeb39119 100644
--- a/compiler/java/com/google/dart/compiler/parser/DartParser.java
+++ b/compiler/java/com/google/dart/compiler/parser/DartParser.java
@@ -4878,6 +4878,7 @@ public class DartParser extends CompletionHooksParserBase {
 
     List<DartSwitchMember> members = new ArrayList<DartSwitchMember>();
     if (peek(0) != Token.LBRACE) {
+      reportUnexpectedToken(position(), Token.LBRACE, peek(0));
       return done(new DartSwitchStatement(expr, members));
     }
     boolean foundOpenBrace = expect(Token.LBRACE);