Doc: shortcut to check JavaScript code syntax

Change-Id: Ifb726f6739a572b927a43065a55986fef0b73c92
Reviewed-by: Christian Kamm <christian.d.kamm@nokia.com>

doc/src/howto/creator-keyboard-shortcuts.qdoc

@@ -350,6 +350,9 @@
         \row
             \o Turn selected text into uppercase
             \o Alt+Shift+U
+        \row
+            \o Run static checks on JavaScript code to find common problems
+            \o Ctrl+Shift+C
     \endtable
 
     \section2 Debugging Keyboard Shortcuts