ui: Rename "All messages" to "Combined feed"

Fixes: #634

Author: Lalit3716

assets/l10n/app_en.arb

@@ -460,9 +460,9 @@
   "@recentDmConversationsPageTitle": {
     "description": "Title for the page of recent DM conversations"
   },
-  "allMessagesPageTitle": "All messages",
-  "@allMessagesPageTitle": {
-    "description": "Title for the page of all messages"
+  "combinedFeedPageTitle": "Combined feed",
+  "@combinedFeedPageTitle": {
+    "description": "Title for the page of combined feed."
   },
   "notifGroupDmConversationLabel": "{senderFullName} to you and {numOthers, plural, =1{1 other} other{{numOthers} others}}",
   "@notifGroupDmConversationLabel": {

lib/widgets/app.dart

@@ -272,7 +272,7 @@ class HomePage extends StatelessWidget {
             onPressed: () => Navigator.push(context,
               MessageListPage.buildRoute(context: context,
                 narrow: const AllMessagesNarrow())),
-            child: Text(zulipLocalizations.allMessagesPageTitle)),
+            child: Text(zulipLocalizations.combinedFeedPageTitle)),
           const SizedBox(height: 16),
           ElevatedButton(
             onPressed: () => Navigator.push(context,

lib/widgets/message_list.dart

@@ -143,7 +143,7 @@ class MessageListAppBarTitle extends StatelessWidget {
 
     switch (narrow) {
       case AllMessagesNarrow():
-        return Text(zulipLocalizations.allMessagesPageTitle);
+        return Text(zulipLocalizations.combinedFeedPageTitle);
 
       case StreamNarrow(:var streamId):
         final store = PerAccountStoreWidget.of(context);