Reverted again the gdk_threads_enter/leave sentences:

Reverted again the gdk_threads_enter/leave sentences:
* src/widgets/modest-attachment-view.c
* src/widgets/modest-header-view.c
* src/maemo/modest-maemo-global-settings-dialog.c
* src/modest-mail-operation.c

Misc changes (mainly work to implement attachment purging):
* src/widgets/modest-msg-view.c:
        * Added find toolbar scroll fix, disabled as we're waiting
          for the new gtkhtml gtk_html_get_selection_area API.
        * Now we don't remove the attached part on removing attachments
          from view.
* src/widgets/modest-attachment-view.c:
        * Added support for showing purged files as purged. The icon is
          the default document one, and the text is a currently non
          translated string.
        * Now size is only shown for file attachments (if they're not
          purged).
* src/maemo/modest-msg-view-window.c:
        * Use the new Tinymail mime part purge API. It purges really the
          attachments. The UI is a work in progress still, but the
          cache seems to get updated as expected. This implementation
          replaces the old delete_attachments tinymail API based
          implementation.
* src/ui/modest-ui-dimming-rules.c:
        * Added some dimming rules for remove attachments in message view.
          It's not complete yet.
        * Now "move to" operation does not check if the source folder is
          writeable (fixes NB#61860).

pmo-trunk-r2460