Flutter project not running after successful migration to null safety - flutter

Question

I have problem running flutter project after successful migration to null safety. I use android studio. Here is the result of flutter doctor:
Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 2.2.1, on Microsoft Windows [Version 10.0.19041.985], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
[√] Chrome - develop for the web
[√] Android Studio (version 4.1.0)
[√] Connected device (3 available)
• No issues found!
And here is the result of outdated dependency checks:
See https://dart.dev/go/null-safety-migration for a migration guide.
Analyzing project...
[-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------\]
All sources appear to be already migrated. Nothing to do.
However, I get an error caused by a dependency (not used directly in my pubspec.yaml, but seems one of the packages is using it and this dependency has no null safety updated). So when I try to run it from android studio I get the following output (even though dart migrate should have mention even internal packages dependencies since it might be a stopper from running):
Launching lib\main.dart on Android SDK built for x86 in debug mode...
Running Gradle task 'assembleDebug'...
Error: Cannot run with sound null safety, because the following dependencies
don't support null safety:
- package:tinycolor
For solutions, see https://dart.dev/go/unsound-null-safety
lib/screens/invitations_screen.dart:115:5: Warning: Operand of null-aware operation '?.' has type 'TabController' which excludes null.
- 'TabController' is from 'package:flutter/src/material/tab_controller.dart' ('/D:/Flutter/flutterV1.0.0.0/packages/flutter/lib/src/material/tab_controller.dart').
_c1?.dispose();
^
/D:/Flutter/flutterV1.0.0.0/.pub-cache/hosted/pub.dartlang.org/flutter_datetime_picker-1.5.1/lib/flutter_datetime_picker.dart:311:32: Warning: Operand of null-aware operation '??' has type 'Color' which excludes null.
- 'Color' is from 'dart:ui'.
color: theme.backgroundColor ?? Colors.white,
^
FAILURE: Build failed with an exception.
* Where:
Script 'D:\Flutter\flutterV1.0.0.0\packages\flutter_tools\gradle\flutter.gradle' line: 1035
* What went wrong:
Execution failed for task ':app:compileFlutterBuildDebug'.
> Process 'command 'D:\Flutter\flutterV1.0.0.0\bin\flutter.bat'' finished with non-zero exit value 1
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 23s
Exception: Gradle task assembleDebug failed with exit code 1
So I tried finally to run without sound-null-safety, but still an error keeps happening (I tried flutter clean --> Invalidate Caches/Restart --> pub get --> flutter run --no-sound-null-safety but still the same problem):
Using hardware rendering with device Android SDK built for x86. If you notice graphics artifacts, consider enabling software rendering with "--enable-software-rendering".
Launching lib\main.dart on Android SDK built for x86 in debug mode...
Running Gradle task 'assembleDebug'...
Running Gradle task 'assembleDebug'... Done 22.1s
√ Built build\app\outputs\flutter-apk\app-debug.apk.
Error connecting to the service protocol: failed to connect to http://127.0.0.1:57596/NxvUCmZt3sM=/
Note: Before the last trial of restarting android studio, this last error also showed an exception right before the "Error connecting ..." statement, and the exception was as I recall (sorry don't have the full stack trace as it doesn't show anymore):
androidx WindowInsetsCompat ---> NullPointerException on Preconditions.checkNonNull
EDIT
After going through dependencies in a new porject as suggested by #Taur, it turns out the problem when running without sound-null-safety was caused by flutter_typeahead dependency throwing the previously mentioned exception when I run the project:
E/AndroidRuntime(11173): java.lang.ExceptionInInitializerError
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat.<clinit>(WindowInsetsCompat.java:82)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat.toWindowInsetsCompat(WindowInsetsCompat.java:169)
E/AndroidRuntime(11173): at androidx.core.view.ViewCompat$Api21Impl$1.onApplyWindowInsets(ViewCompat.java:4753)
E/AndroidRuntime(11173): at android.view.View.dispatchApplyWindowInsets(View.java:9799)
E/AndroidRuntime(11173): at android.view.ViewGroup.dispatchApplyWindowInsets(ViewGroup.java:7076)
E/AndroidRuntime(11173): at android.view.ViewGroup.dispatchApplyWindowInsets(ViewGroup.java:7080)
E/AndroidRuntime(11173): at android.view.ViewGroup.dispatchApplyWindowInsets(ViewGroup.java:7080)
E/AndroidRuntime(11173): at android.view.ViewRootImpl.dispatchApplyInsets(ViewRootImpl.java:1632)
E/AndroidRuntime(11173): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1734)
E/AndroidRuntime(11173): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1443)
E/AndroidRuntime(11173): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7125)
E/AndroidRuntime(11173): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:935)
E/AndroidRuntime(11173): at android.view.Choreographer.doCallbacks(Choreographer.java:747)
E/AndroidRuntime(11173): at android.view.Choreographer.doFrame(Choreographer.java:682)
E/AndroidRuntime(11173): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:921)
E/AndroidRuntime(11173): at android.os.Handler.handleCallback(Handler.java:873)
E/AndroidRuntime(11173): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(11173): at android.os.Looper.loop(Looper.java:164)
E/AndroidRuntime(11173): at android.app.ActivityThread.main(ActivityThread.java:6649)
E/AndroidRuntime(11173): at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(11173): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
E/AndroidRuntime(11173): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:826)
E/AndroidRuntime(11173): Caused by: java.lang.NullPointerException
E/AndroidRuntime(11173): at androidx.core.util.Preconditions.checkNotNull(Preconditions.java:119)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat.toWindowInsetsCompat(WindowInsetsCompat.java:169)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat.toWindowInsetsCompat(WindowInsetsCompat.java:149)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat$BuilderImpl20.build(WindowInsetsCompat.java:1706)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat$Builder.build(WindowInsetsCompat.java:1588)
E/AndroidRuntime(11173): at androidx.core.view.WindowInsetsCompat$Impl.<clinit>(WindowInsetsCompat.java:748)
E/AndroidRuntime(11173): ... 22 more