Improve on previous strategy for better protecting undo

This protects against other similar "indent on very next command"
problems similar to the one described in Malabarba#119.

* aggressive-indent.el
(aggressive-indent--proccess-changed-list-and-indent): Clear
aggressive-indent--changed-list.
(aggressive-indent--keep-track-of-changes): Don't check undo-in-progress

aggressive-indent.el

@@ -389,8 +389,9 @@ or messages."
 
 (defun aggressive-indent--proccess-changed-list-and-indent ()
   "Indent the regions in `aggressive-indent--changed-list'."
-  (unless (or (run-hook-wrapped 'aggressive-indent--internal-dont-indent-if #'eval)
-              (aggressive-indent--run-user-hooks))
+  (if (or (run-hook-wrapped 'aggressive-indent--internal-dont-indent-if #'eval)
+          (aggressive-indent--run-user-hooks))
+      (setq aggressive-indent--changed-list nil) ;; forget any past changes
     (let ((inhibit-modification-hooks t)
           (inhibit-point-motion-hooks t)
           (indent-function
@@ -426,8 +427,7 @@ typing, try tweaking this number."
 (defun aggressive-indent--keep-track-of-changes (l r &rest _)
   "Store the limits (L and R) of each change in the buffer."
   (when aggressive-indent-mode
-    (unless undo-in-progress
-      (push (list l r) aggressive-indent--changed-list))
+    (push (list l r) aggressive-indent--changed-list)
     (unless (timerp aggressive-indent--idle-timer)
       (setq aggressive-indent--idle-timer
             (run-with-idle-timer aggressive-indent-sit-for-time t #'aggressive-indent--indent-if-changed)))))