Made the actual implementation of the lexical classifier be non-optional.

Author: DanielRosenwasser

src/services/services.ts

@@ -5680,7 +5680,7 @@ module ts {
                     keyword2 === SyntaxKind.ConstructorKeyword ||
                     keyword2 === SyntaxKind.StaticKeyword) {
 
-                    // Allow things like  "public get", "public constructor" and "public static".  
+                    // Allow things like "public get", "public constructor" and "public static".  
                     // These are all legal.
                     return true;
                 }
@@ -5697,7 +5697,7 @@ module ts {
 
         // If there is a syntactic classifier ('syntacticClassifierAbsent' is false),
         // we will be more conservative in order to avoid conflicting with the syntactic classifier.
-        function getClassificationsForLine(text: string, lexState: EndOfLineState, syntacticClassifierAbsent?: boolean): ClassificationResult {
+        function getClassificationsForLine(text: string, lexState: EndOfLineState, syntacticClassifierAbsent: boolean): ClassificationResult {
             var offset = 0;
             var token = SyntaxKind.Unknown;
             var lastNonTriviaToken = SyntaxKind.Unknown;