home: Replace SizeBox with ConstrainedBox in bottom nav bar

This allows the height of bottom nav bar
to dyanmically change on the basis of system
font size, maxHeight has been set after calibration.

Author: MritunjayTiwari14

lib/widgets/home.dart

@@ -142,17 +142,15 @@ class _HomePageState extends State<HomePage> {
           border: Border(top: BorderSide(color: designVariables.borderBar)),
           color: designVariables.bgBotBar),
         child: SafeArea(
-          child: SizedBox(height: 48,
-            child: Center(
-              child: ConstrainedBox(
-                // TODO(design): determine a suitable max width for bottom nav bar
-                constraints: const BoxConstraints(maxWidth: 600),
-                child: Row(
-                  crossAxisAlignment: CrossAxisAlignment.stretch,
-                  children: [
-                    for (final navigationBarButton in navigationBarButtons)
-                      Expanded(child: navigationBarButton),
-                  ])))))));
+          child: ConstrainedBox(
+            // TODO(design): determine a suitable max width for bottom nav bar
+            constraints: const BoxConstraints(maxWidth: 600, minHeight: 48, maxHeight: 85),
+            child: Row(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                for (final navigationBarButton in navigationBarButtons)
+                  Expanded(child: navigationBarButton),
+              ])))));
   }
 }
 

test/widgets/recent_dm_conversations_test.dart

@@ -58,7 +58,7 @@ Future<void> setupPage(WidgetTester tester, {
 
   // Switch to direct messages tab.
   await tester.tap(find.descendant(
-    of: find.byType(Center),
+    of: find.byType(DecoratedBox),
     matching: find.byIcon(ZulipIcons.two_person)));
   await tester.pump();
 }