hterm: fix console warning

Change-Id: I98773ff3e9e26b18434cbef68024c6a36a3f06c4
Reviewed-on: https://chromium-review.googlesource.com/636401
Reviewed-by: Brandon Gilmore <varz@google.com>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/hterm/js/hterm_terminal.js b/hterm/js/hterm_terminal.js
index aa45e2e..6851b27 100644
--- a/hterm/js/hterm_terminal.js
+++ b/hterm/js/hterm_terminal.js
@@ -3096,7 +3096,7 @@
       if ((this.mouseRightClickPaste && e.button == 2 /* right button */) ||
           e.button == this.mousePasteButton) {
         if (!this.paste())
-          console.warning('Could not paste manually due to web restrictions');;
+          console.warn('Could not paste manually due to web restrictions');
       }
     }