boxes/views: Keep the log focus constant while the search is active.

This amends update_streams and update_topics to set the log focus to the
start while the search is active.

NOTE: Sets a regression in the focus_index_before_search logic where now
the list shifts itself after 'esc' is pressed.

Author: preetmishra

zulipterminal/ui_tools/boxes.py

@@ -1212,6 +1212,13 @@ def reset_search_text(self) -> None:
         self.set_caption('')
         self.set_edit_text(self.search_text)
 
+    def reset_active_search_focus(self) -> None:
+        """
+        Sets focus to the start on every callback to update_function.
+        """
+        if len(self.panel_view.log):
+            self.panel_view.body.set_focus(0)
+
     def keypress(self, size: urwid_Size, key: str) -> Optional[str]:
         if ((is_command_key('ENTER', key)
              and self.get_edit_text().lstrip() == '')

zulipterminal/ui_tools/views.py

@@ -317,6 +317,7 @@ def update_streams(self, search_box: Any, new_text: str) -> None:
 
             self.log.clear()
             self.log.extend(streams_display)
+            self.stream_search_box.reset_active_search_focus()
             self.view.controller.update_screen()
 
     def mouse_event(self, size: urwid_Size, event: str, button: int, col: int,
@@ -386,6 +387,7 @@ def update_topics(self, search_box: Any, new_text: str) -> None:
             ]
             self.log.clear()
             self.log.extend(topics_to_display)
+            self.topic_search_box.reset_active_search_focus()
             self.view.controller.update_screen()
 
     def update_topics_list(self, stream_id: int, topic_name: str,