Add more coverage tests.

src/compiler/checker.ts

@@ -1033,10 +1033,6 @@ module ts {
             writer.writePunctuation(tokenToString(kind));
         }
 
-        function writeOperator(writer: SymbolWriter, kind: SyntaxKind) {
-            writer.writeOperator(tokenToString(kind));
-        }
-
         function writeSpace(writer: SymbolWriter) {
             writer.writeSpace(" ");
         }
@@ -7820,8 +7816,10 @@ module ts {
         }
 
         function checkThrowStatement(node: ThrowStatement) {
-            checkExpression(node.expression);
-        }
+            if (node.expression) {
+                checkExpression(node.expression);
+            }
+}
 
         function checkTryStatement(node: TryStatement) {
             checkBlock(node.tryBlock);

src/harness/harness.ts

@@ -27,6 +27,7 @@ var _chai: typeof chai = require('chai');
 var assert: typeof _chai.assert = _chai.assert;
 declare var __dirname: any; // Node-specific
 var global = <any>Function("return this").call(null);
+var typescript = require('./typescriptServices');
 
 module Utils {
     var global = <any>Function("return this").call(null);
@@ -1389,7 +1390,4 @@ module Harness {
     }
 
     if (Error) (<any>Error).stackTraceLimit = 1;
-}
-
-// TODO: not sure why Utils.evalFile isn't working with this, eventually will concat it like old compiler instead of eval
-eval(Harness.tcServicesFile);
+}