Bug 1727484 - Convert the "Send Tab to Device" string in the tab context menu to title case. r=Gijs,fluent-reviewers

Differential Revision: https://phabricator.services.mozilla.com/D124131

browser/base/content/browser-sync.js

@@ -1543,12 +1543,9 @@ var gSync = {
       let tabCount = aTargetTab.multiselected
         ? gBrowser.multiSelectedTabsCount
         : 1;
-      sendTabsToDevice.label = PluralForm.get(
-        tabCount,
-        gNavigatorBundle.getString("sendTabsToDevice.label")
-      ).replace("#1", tabCount.toLocaleString());
-      sendTabsToDevice.accessKey = gNavigatorBundle.getString(
-        "sendTabsToDevice.accesskey"
+      sendTabsToDevice.setAttribute(
+        "data-l10n-args",
+        JSON.stringify({ tabCount })
       );
       sendTabsToDevice.hidden = false;
     }

browser/base/content/main-popupset.inc.xhtml

@@ -54,7 +54,9 @@
       </menupopup>
     </menu>
     <menu id="context_sendTabToDevice"
-          class="sync-ui-item">
+          class="sync-ui-item"
+          data-lazy-l10n-id="tab-context-send-tabs-to-device"
+          data-l10n-args='{"tabCount": 1}'>
       <menupopup id="context_sendTabToDevicePopupMenu"
                  onpopupshowing="gSync.populateSendTabToDevicesMenu(event.target, TabContextMenu.contextTab.linkedBrowser.currentURI.spec, TabContextMenu.contextTab.linkedBrowser.contentTitle, TabContextMenu.contextTab.multiselected);"/>
     </menu>

browser/locales/en-US/browser/tabContextMenu.ftl

@@ -94,3 +94,11 @@ tab-context-move-tabs =
            *[other] Move Tabs
         }
     .accesskey = v
+
+tab-context-send-tabs-to-device =
+    .label =
+        { $tabCount ->
+            [1] Send Tab to Device
+           *[other] Send { $tabCount } Tabs to Device
+        }
+    .accessKey = n