Emit pinned/tripleslash reference comments of interfaces

Fixes #501

Author: sheetalkamat

src/compiler/emitter.ts

@@ -1682,6 +1682,10 @@ module ts {
                 }
             }
 
+            function emitInterfaceDeclaration(node: InterfaceDeclaration) {
+                emitPinnedOrTripleSlashComments(node);
+            }
+
             function emitEnumDeclaration(node: EnumDeclaration) {
                 emitLeadingComments(node);
                 if (!(node.flags & NodeFlags.Export)) {
@@ -2089,6 +2093,8 @@ module ts {
                         return emitVariableDeclaration(<VariableDeclaration>node);
                     case SyntaxKind.ClassDeclaration:
                         return emitClassDeclaration(<ClassDeclaration>node);
+                    case SyntaxKind.InterfaceDeclaration:
+                        return emitInterfaceDeclaration(<InterfaceDeclaration>node);
                     case SyntaxKind.EnumDeclaration:
                         return emitEnumDeclaration(<EnumDeclaration>node);
                     case SyntaxKind.ModuleDeclaration:

tests/baselines/reference/checkInterfaceBases.js

@@ -16,3 +16,4 @@ interface Third extends JQueryEventObjectTest, SecondEvent {}
 
 
 //// [app.js]
+///<reference path='jquery.d.ts' />

tests/baselines/reference/commentOnInterface1.js

@@ -1,10 +1,20 @@
-//// [commentOnInterface1.ts]
+//// [tests/cases/compiler/commentOnInterface1.ts] ////
+
+//// [a.ts]
 /*! Keep this pinned comment */
 interface I {
 }
 
 // Don't keep this comment.
 interface I2 {
+}
+
+//// [b.ts]
+///<reference path='a.ts'/>
+interface I3 {
 }
 
-//// [commentOnInterface1.js]
+//// [a.js]
+/*! Keep this pinned comment */
+//// [b.js]
+///<reference path='a.ts'/>

tests/baselines/reference/commentOnInterface1.types

@@ -1,4 +1,9 @@
-=== tests/cases/compiler/commentOnInterface1.ts ===
+=== tests/cases/compiler/b.ts ===
+///<reference path='a.ts'/>
+interface I3 {
+>I3 : I3
+}
+=== tests/cases/compiler/a.ts ===
 /*! Keep this pinned comment */
 interface I {
 >I : I
@@ -8,3 +13,4 @@ interface I {
 interface I2 {
 >I2 : I2
 }
+

tests/cases/compiler/commentOnInterface1.ts

@@ -1,7 +1,13 @@
+//@filename: a.ts
 /*! Keep this pinned comment */
 interface I {
 }
 
 // Don't keep this comment.
 interface I2 {
+}
+
+//@filename: b.ts
+///<reference path='a.ts'/>
+interface I3 {
 }