Reverts: #162315

Initiated by: TahaTesser

Reason for reverting: Red tree due to unapproved golden images.

Original PR Author: TahaTesser

Reviewed By: {justinmc}

This change reverts the following previous change:
Fixes #162098

Description

This PR fixes Tab linear and elastic animation blinks/flickers when skipping multiple tabs. Previous attempt to fix elastic animation didn't cover linear animation tests and didn't have enough number of tab items which this PR fixes.

• Fixed Linear and elastic animation blink issue.
• Added tests for linear and elastic animation with various tab sizes (LTR and RTL)
• Added tests for linear and elastic animation when skipping tabs (LTR and RTL)

Code Sample

import 'package:flutter/material.dart';
// import 'package:flutter/scheduler.dart';

void main() {
  // timeDilation = 10;
  runApp(const TabBarDemo());
}

class TabBarDemo extends StatelessWidget {
  const TabBarDemo({super.key});

  @override
  Widget build(BuildContext context) {
    final List<Widget> tabs = <Widget>[
      const Tab(text: 'Short'),
      const Tab(text: 'A Bit Longer Text'),
      const Tab(text: 'An Extremely Long Tab Label That Overflows'),
      const Tab(text: 'Tiny'),
      const Tab(text: 'Moderate Length'),
      const Tab(text: 'Just Right'),
      const Tab(text: 'Supercalifragilisticexpialidocious'),
      const Tab(text: 'Longer Than Usual'),
    ];

    return MaterialApp(
      home: DefaultTabController(
        length: tabs.length,
        child: Scaffold(
          appBar: AppBar(
            bottom: TabBar(
              tabAlignment: TabAlignment.start,
              isScrollable: true,
              indicatorAnimation: TabIndicatorAnimation.elastic,
              tabs: tabs,
            ),
            title: const Text('Tabs Demo'),
          ),
          body: TabBarView(
            children: <Widget>[
              for (int i = 0; i < tabs.length; i++) const Icon(Icons.directions_car),
            ],
          ),
        ),
      ),
    );
  }
}

Before

After

Linear animation before (left) and After (right) comparison.

Pre-launch Checklist

• I read the Contributor Guide and followed the process outlined there for submitting PRs.
• I read the Tree Hygiene wiki page, which explains my responsibilities.
• I read and followed the Flutter Style Guide, including Features we expect every widget to implement.
• I signed the CLA.
• I listed at least one issue that this PR fixes in the description above.
• I updated/added relevant documentation (doc comments with ///).
• I added new tests to check the change I am making, or this PR is test-exempt.
• I followed the breaking change policy and added Data Driven Fixes where supported.
• All existing and new tests are passing.

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