Report error on unclosed multiline comment.

Fixes #22

Author: DanielRosenwasser

src/compiler/scanner.ts

@@ -662,11 +662,14 @@ module ts {
                         if (text.charCodeAt(pos + 1) === CharacterCodes.asterisk) {
                             pos += 2;
 
-                            while (pos < len) {
+                            var safeLength = len - 1; // For lookahead.
+                            var commentClosed = false;
+                            while (pos < safeLength) {
                                 var ch = text.charCodeAt(pos);
 
                                 if (ch === CharacterCodes.asterisk && text.charCodeAt(pos + 1) === CharacterCodes.slash) {
                                     pos += 2;
+                                    commentClosed = true;
                                     break;
                                 }
 
@@ -676,6 +679,11 @@ module ts {
                                 pos++;
                             }
 
+                            if (!commentClosed) {
+                                pos++;
+                                onError(Diagnostics.Asterisk_Slash_expected);
+                            }
+
                             if (onComment) {
                                 onComment(tokenPos, pos);
                             }

tests/baselines/reference/parserKeywordsAsIdentifierName2.errors.txt

@@ -0,0 +1,7 @@
+==== tests/cases/conformance/parser/ecmascript5/parserKeywordsAsIdentifierName2.ts (2 errors) ====
+    // 'public' should be marked unusable, should complain on trailing /*
+    a.public /*
+               
+!!! '*/' expected.
+    ~
+!!! Cannot find name 'a'.

tests/baselines/reference/parserKeywordsAsIdentifierName2.js

@@ -0,0 +1,17 @@
+==== tests/cases/conformance/scanner/ecmascript5/scannerS7.4_A2_T2.ts (1 errors) ====
+    // Copyright 2009 the Sputnik authors.  All rights reserved.
+    // This code is governed by the BSD license found in the LICENSE file.
+    
+    /**
+     * Correct interpretation of multi line comments
+     *
+     * @path ch07/7.4/S7.4_A2_T2.js
+     * @description Try use /*CHECK#1/. This is not closed multi line comment
+     * @negative
+     */
+    
+    /*CHECK#1/
+    
+    
+    
+!!! '*/' expected.

tests/baselines/reference/scannerS7.4_A2_T2.errors.txt

@@ -1,2 +1,2 @@
-// 'public' shoudl be marked unusable because it has a trailing /*
-//a.public /*
+// 'public' should be marked unusable, should complain on trailing /*
+a.public /*