Issue 1179: Actions do not move the program counter after Step Into if breakpoint is on first line of function

Steps to reproduce

  1. Open Firebug, enable the Script panel and reload the page.
  2. Create a breakpoint on lines 14 and 21
  3. Press this button
  4. Debugger should halt at line 14
  5. Step Into should go to line 21
  6. Step Out should go to line 14
  7. Step Into should go to line 15
  8. Step Over should go to line 16