Donate buttons should link to localized donate pages

Fixes #1819064 [Clicking on the heart (donate) button will not get you to the donate page in your language](https://bugs.launchpad.net/calibre/+bug/1819064)

src/calibre/gui2/tweak_book/ui.py

@@ -47,11 +47,11 @@ from calibre.gui2.tweak_book.editor.widget import register_text_editor_actions
 from calibre.gui2.tweak_book.editor.insert_resource import InsertImage
 from calibre.utils.icu import sort_key, ord_string
 from calibre.utils.unicode_names import character_name_from_code
-from calibre.utils.localization import localize_user_manual_link
+from calibre.utils.localization import localize_user_manual_link, localize_website_link
 
 
 def open_donate():
-    open_url(QUrl('https://calibre-ebook.com/donate'))
+    open_url(QUrl(localize_website_link('https://calibre-ebook.com/donate')))
 
 
 class Central(QStackedWidget):  # {{{

src/calibre/gui2/ui.py

@@ -922,7 +922,8 @@ class Main(MainWindow, MainWindowMixin, DeviceMixin, EmailMixin,  # {{{
         QApplication.instance().quit()
 
     def donate(self, *args):
-        open_url(QUrl('https://calibre-ebook.com/donate'))
+        from calibre.utils.localization import localize_website_link
+        open_url(QUrl(localize_website_link('https://calibre-ebook.com/donate')))
 
     def confirm_quit(self):
         if self.job_manager.has_jobs():

src/calibre/srv/code.py

@@ -27,7 +27,7 @@ from calibre.srv.routes import endpoint, json
 from calibre.srv.utils import get_library_data, get_use_roman
 from calibre.utils.config import prefs, tweaks
 from calibre.utils.icu import sort_key, numeric_sort_key
-from calibre.utils.localization import get_lang, lang_map_for_ui
+from calibre.utils.localization import get_lang, lang_map_for_ui, localize_website_link
 from calibre.utils.search_query_parser import ParseException
 
 POSTABLE = frozenset({'GET', 'POST', 'HEAD'})
@@ -150,6 +150,7 @@ def basic_interface_data(ctx, rd):
         'custom_list_template': getattr(ctx, 'custom_list_template', None) or custom_list_template(),
         'search_the_net_urls': getattr(ctx, 'search_the_net_urls', None) or [],
         'num_per_page': rd.opts.num_per_page,
+        'donate_link': localize_website_link('https://calibre-ebook.com/donate')
     }
     ans['library_map'], ans['default_library_id'] = ctx.library_info(rd)
     return ans

src/pyj/book_list/top_bar.pyj

@@ -6,6 +6,7 @@ from book_list.theme import get_color, get_font_size
 from dom import set_css, clear, create_keyframes, build_rule, svgicon, add_extra_css
 from elementmaker import E
 from gettext import gettext as _
+from session import get_interface_data
 
 bar_counter = 0
 CLASS_NAME = 'main-top-bar'
@@ -50,6 +51,7 @@ def set_left_data(container, title='calibre', icon='heart', action=None, tooltip
     if icon is 'heart':
         if not tooltip:
             tooltip = _('Donate to support calibre development')
+    interface_data = get_interface_data()
 
     for i, bar in enumerate(bars):
         left = bar.firstChild
@@ -66,7 +68,7 @@ def set_left_data(container, title='calibre', icon='heart', action=None, tooltip
                     animation_iteration_count='5', animation_play_state='running' if run_animation else 'paused'
                 )
                 set_css(a.firstChild, color=get_color('heart'))
-                a.setAttribute('href', 'https://calibre-ebook.com/donate')
+                a.setAttribute('href', interface_data.donate_link)
                 a.setAttribute('target', 'donate-to-calibre')
             if action is not None:
                 a.addEventListener('click', def(event): event.preventDefault(), action();)

src/pyj/session.pyj

@@ -170,6 +170,7 @@ default_interface_data = {
     'default_library_id': None,
     'library_map': None,
     'search_the_net_urls': [],
+    'donate_link': 'https://calibre-ebook.com/donate',
     'icon_map': {},
     'icon_path': '',
     'custom_list_template': None,