Ignore right mouse button in click on a line number in diff

Test Plan:
Go to any diff
Click on a line number with right mouse button
No dialog should be opened

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, epriestley

Differential Revision: 1150

webroot/rsrc/js/application/differential/behavior-edit-inline-comments.js

@@ -75,6 +75,7 @@ JX.behavior('differential-edit-inline-comments', function(config) {
     function(e) {
       if (editor  ||
           selecting ||
+          e.isRightButton() ||
           getRowNumber(e.getTarget()) === undefined) {
         return;
       }