Account for typeof expressions, added test.

src/services/utilities.ts

@@ -160,8 +160,10 @@ module ts {
                 }
                 return isCompletedNode((<DoStatement>n).statement, sourceFile);
 
+            case SyntaxKind.TypeOfExpression:
+                return isCompletedNode((<TypeOfExpression>n).expression, sourceFile);
             case SyntaxKind.PrefixUnaryExpression:
-                return isCompletedNode(<PrefixUnaryExpression>n, sourceFile);
+                return isCompletedNode((<PrefixUnaryExpression>n).operand, sourceFile);
             case SyntaxKind.BinaryExpression:
                 return isCompletedNode((<BinaryExpression>n).right, sourceFile);
             case SyntaxKind.ConditionalExpression:

tests/cases/fourslash/completionListInUnclosedIndexSignature01.ts

@@ -5,7 +5,6 @@
 ////    [foo: string]: typeof /*1*/
 ////}
 
-
 goTo.marker("1");
 verify.completionListContains("foo");
 verify.completionListContains("C");

tests/cases/fourslash/completionListInUnclosedIndexSignature03.ts

@@ -0,0 +1,10 @@
+/// <reference path='fourslash.ts' />
+
+
+////class C {
+////    [foo: string]: { x: typeof /*1*/
+////}
+
+goTo.marker("1");
+verify.completionListContains("foo");
+verify.completionListContains("C");