Add isDefinition to ReferenceEntry

Clients can now easily tell if the reference is to a definition or a
usage.

src/server/client.ts

@@ -376,6 +376,7 @@ namespace ts.server {
                     fileName: fileName,
                     textSpan: ts.createTextSpanFromBounds(start, end),
                     isWriteAccess: entry.isWriteAccess,
+                    isDefinition: entry.isDefinition,
                 };
             });
         }

src/server/protocol.d.ts

@@ -304,6 +304,11 @@ declare namespace ts.server.protocol {
           * True if reference is a write location, false otherwise.
           */
         isWriteAccess: boolean;
+
+        /**
+         * True if reference is a definition, false otherwise.
+         */
+        isDefinition?: boolean;
     }
 
     /**

src/server/session.ts

@@ -379,7 +379,7 @@ namespace ts.server {
                     start,
                     end,
                     file: fileName,
-                    isWriteAccess
+                    isWriteAccess,
                 };
             });
         }
@@ -555,7 +555,8 @@ namespace ts.server {
                             start: start,
                             lineText: lineText,
                             end: compilerService.host.positionToLineOffset(ref.fileName, ts.textSpanEnd(ref.textSpan)),
-                            isWriteAccess: ref.isWriteAccess
+                            isWriteAccess: ref.isWriteAccess,
+                            isDefinition: ref.isDefinition
                         };
                     });
                 },