[geary/wip/cdavis/status-page] conversation-viewer: Use HdyStatusPage for empty states

[Christopher Davis <christopherdavis src gnome org>]

commit b1fdf2aa2962ba2706d952b90f2038adfcda32ef
Author: Christopher Davis <brainblasted disroot org>
Date:   Sat Feb 6 03:51:09 2021 -0800

    conversation-viewer: Use HdyStatusPage for empty states
    
    Libhandy now has a pre-built widget for empty states.
    We should use that instead of a custom empty state.

 meson.build                                        |  2 +-
 .../conversation-viewer/conversation-viewer.vala   | 52 +++++++++++++---------
 2 files changed, 33 insertions(+), 21 deletions(-)
---
diff --git a/meson.build b/meson.build
index 37b527095..2deff16df 100644
--- a/meson.build
+++ b/meson.build
@@ -89,7 +89,7 @@ icu_uc = dependency('icu-uc', version: '>=60')
 iso_codes = dependency('iso-codes')
 javascriptcoregtk = dependency('javascriptcoregtk-4.0', version: '>=' + target_webkit)
 json_glib = dependency('json-glib-1.0', version: '>= 1.0')
-libhandy = dependency('libhandy-1', version: '>= 0.90')
+libhandy = dependency('libhandy-1', version: '>= 1.1.0')
 libmath = cc.find_library('m')
 libpeas = dependency('libpeas-1.0', version: '>= 1.24.0')
 libpeas_gtk = dependency('libpeas-gtk-1.0', version: '>= 1.24.0')
diff --git a/src/client/conversation-viewer/conversation-viewer.vala 
b/src/client/conversation-viewer/conversation-viewer.vala
index 4d895db46..bc7966fa7 100644
--- a/src/client/conversation-viewer/conversation-viewer.vala
+++ b/src/client/conversation-viewer/conversation-viewer.vala
@@ -87,56 +87,68 @@ public class ConversationViewer : Gtk.Stack, Geary.BaseInterface {
         base_ref();
         this.config = config;
 
-        Components.PlaceholderPane no_conversations =
-            new Components.PlaceholderPane();
+        Hdy.StatusPage no_conversations =
+            new Hdy.StatusPage();
         no_conversations.icon_name = "folder-symbolic";
         // Translators: Title label for placeholder when no
         // conversations have been selected.
-        no_conversations.title = _("No conversations selected");
+        no_conversations.title = _("No Conversations Selected");
         // Translators: Sub-title label for placeholder when no
         // conversations have been selected.
-        no_conversations.subtitle = _(
-            "Selecting a conversation from the list will display it here"
+        no_conversations.description = _(
+            "Selecting a conversation from the list will display it here."
         );
+        no_conversations.hexpand = true;
+        no_conversations.vexpand = true;
+        no_conversations.show ();
         this.no_conversations_page.add(no_conversations);
 
-        Components.PlaceholderPane multi_conversations =
-            new Components.PlaceholderPane();
+        Hdy.StatusPage multi_conversations =
+            new Hdy.StatusPage();
         multi_conversations.icon_name = "folder-symbolic";
         // Translators: Title label for placeholder when multiple
         // conversations have been selected.
-        multi_conversations.title = _("Multiple conversations selected");
+        multi_conversations.title = _("Multiple Conversations Selected");
         // Translators: Sub-title label for placeholder when multiple
         // conversations have been selected.
-        multi_conversations.subtitle = _(
-            "Choosing an action will apply to all selected conversations"
+        multi_conversations.description = _(
+            "Choosing an action will apply to all selected conversations."
         );
+        multi_conversations.hexpand = true;
+        multi_conversations.vexpand = true;
+        multi_conversations.show ();
         this.multiple_conversations_page.add(multi_conversations);
 
-        Components.PlaceholderPane empty_folder =
-            new Components.PlaceholderPane();
+        Hdy.StatusPage empty_folder =
+            new Hdy.StatusPage();
         empty_folder.icon_name = "folder-symbolic";
         // Translators: Title label for placeholder when no
         // conversations have exist in a folder.
-        empty_folder.title = _("No conversations found");
+        empty_folder.title = _("No Conversations Found");
         // Translators: Sub-title label for placeholder when no
         // conversations have exist in a folder.
-        empty_folder.subtitle = _(
-            "This folder does not contain any conversations"
+        empty_folder.description = _(
+            "This folder does not contain any conversations."
         );
+        empty_folder.hexpand = true;
+        empty_folder.vexpand = true;
+        empty_folder.show ();
         this.empty_folder_page.add(empty_folder);
 
-        Components.PlaceholderPane empty_search =
-            new Components.PlaceholderPane();
+        Hdy.StatusPage empty_search =
+            new Hdy.StatusPage();
         empty_search.icon_name = "folder-symbolic";
         // Translators: Title label for placeholder when no
         // conversations have been found in a search.
-        empty_search.title = _("No conversations found");
+        empty_search.title = _("No Conversations Found");
         // Translators: Sub-title label for placeholder when no
         // conversations have been found in a search.
-        empty_search.subtitle = _(
-            "Your search returned no results, try refining your search terms"
+        empty_search.description = _(
+            "Your search returned no results, try refining your search terms."
         );
+        empty_search.hexpand = true;
+        empty_search.vexpand = true;
+        empty_search.show ();
         this.empty_search_page.add(empty_search);
 
         this.conversation_find_undo = new Components.EntryUndo(