An application subclasses edit control and crashes on unexpected WM_TIMER messages. A timer was
added a long time ago and it was for auto scrolling the view when the cursor is outside of the
client area. However, with a EDIT_EM_ScrollCaret() call in EDIT_WM_MouseMove(), the view can be
scrolled to the correct position automatically. So the timer is not necessary at all. This is tested
manually with a long text in the edit control with notepad on XP, Win7 and Win10. Before this patch,
the caret will move backwards every 100ms when the clicking the left mouse button on the bottom of
the text and then dragging the cursor upwards and outside of the client area. After this, the
behavior is the same as native.