adding complete message in documentation [ci skip]

actionpack/lib/abstract_controller/base.rb

@@ -120,7 +120,7 @@ def method_added(name)
     #
     # The actual method that is called is determined by calling
     # #method_for_action. If no method can handle the action, then an
-    # ActionNotFound error is raised.
+    # AbstractController::ActionNotFound error is raised.
     #
     # ==== Returns
     # * <tt>self</tt>
@@ -215,7 +215,8 @@ def _handle_action_missing(*args)
       #
       # ==== Returns
       # * <tt>string</tt> - The name of the method that handles the action
-      # * false           - No valid method name could be found. Raise ActionNotFound.
+      # * false           - No valid method name could be found.
+      # Raise AbstractController::ActionNotFound.
       def _find_action_name(action_name)
         _valid_action_name?(action_name) && method_for_action(action_name)
       end
@@ -235,7 +236,7 @@ def _find_action_name(action_name)
       # the case.
       #
       # If none of these conditions are true, and method_for_action
-      # returns nil, an ActionNotFound exception will be raised.
+      # returns nil, an AbstractController::ActionNotFound exception will be raised.
       #
       # ==== Parameters
       # * <tt>action_name</tt> - An action name to find a method name for