Issue 1:
My screen is working fine but after Flutter upgrade having padding issue in most of screen and another issue is:

Performing hot reload...
Syncing files to device Android SDK built for x86...
I/flutter ( 8606): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter ( 8606): The following assertion was thrown building Products(state: _ProductsState#70260):
I/flutter ( 8606): A GlobalKey was used multiple times inside one widget's child list.
I/flutter ( 8606): The offending GlobalKey was: [LabeledGlobalKey<ScaffoldState>#c2a38]
I/flutter ( 8606): The parent of the widgets with that key was:
I/flutter ( 8606): Products(state: _ProductsState#70260)
I/flutter ( 8606): The first child to get instantiated with that key became:
I/flutter ( 8606): Scaffold-[LabeledGlobalKey<ScaffoldState>#c2a38](state: ScaffoldState#0898d(tickers: tracking 1
I/flutter ( 8606): ticker))
I/flutter ( 8606): The second child that was to be instantiated with that key was:
I/flutter ( 8606): Products
I/flutter ( 8606): A GlobalKey can only be specified on one widget at a time in the widget tree.
I/flutter ( 8606):
I/flutter ( 8606): When the exception was thrown, this was the stack:
I/flutter ( 8606): #0 Element._retakeInactiveElement.<anonymous closure> (package:flutter/src/widgets/framework.dart:2866:11)
I/flutter ( 8606): #1 Element._retakeInactiveElement (package:flutter/src/widgets/framework.dart:2880:8)
I/flutter ( 8606): #2 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2908:32)
I/flutter ( 8606): #3 Element.updateChild (package:flutter/src/widgets/framework.dart:2723:12)
I/flutter ( 8606): #4 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #5 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #6 StatefulElement.update (package:flutter/src/widgets/framework.dart:3812:5)
I/flutter ( 8606): #7 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #8 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #9 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #10 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #11 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #12 StatelessElement.update (package:flutter/src/widgets/framework.dart:3715:5)
I/flutter ( 8606): #13 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #14 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #15 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #16 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #17 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #18 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #19 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #20 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #21 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #22 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #23 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #24 StatefulElement.update (package:flutter/src/widgets/framework.dart:3812:5)
I/flutter ( 8606): #25 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #26 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #27 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #28 StatelessElement.update (package:flutter/src/widgets/framework.dart:3715:5)
I/flutter ( 8606): #29 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #30 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #31 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #32 StatefulElement.update (package:flutter/src/widgets/framework.dart:3812:5)
I/flutter ( 8606): #33 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #34 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #35 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #36 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #37 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #38 ProxyElement.update (package:flutter/src/widgets/framework.dart:3922:5)
I/flutter ( 8606): #39 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #40 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #41 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #42 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #43 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #44 StatefulElement.update (package:flutter/src/widgets/framework.dart:3812:5)
I/flutter ( 8606): #45 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #46 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #47 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #48 StatelessElement.update (package:flutter/src/widgets/framework.dart:3715:5)
I/flutter ( 8606): #49 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #50 SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4674:14)
I/flutter ( 8606): #51 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #52 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #53 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #54 ProxyElement.update (package:flutter/src/widgets/framework.dart:3922:5)
I/flutter ( 8606): #55 Element.updateChild (package:flutter/src/widgets/framework.dart:2712:15)
I/flutter ( 8606): #56 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3666:16)
I/flutter ( 8606): #57 Element.rebuild (package:flutter/src/widgets/framework.dart:3508:5)
I/flutter ( 8606): #58 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2255:33)
I/flutter ( 8606): #59 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding&WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:653:20)
I/flutter ( 8606): #60 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:214:5)
I/flutter ( 8606): #61 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15)
I/flutter ( 8606): #62 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9)
I/flutter ( 8606): #63 _WidgetsFlutterBinding&BindingBase&GestureBinding&ServicesBinding&SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:751:7)
I/flutter ( 8606): #65 _Timer._runTimers (dart:isolate/runtime/libtimer_impl.dart:382:19)
I/flutter ( 8606): #66 _Timer._handleMessage (dart:isolate/runtime/libtimer_impl.dart:416:5)
I/flutter ( 8606): #67 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/libisolate_patch.dart:169:12)
I/flutter ( 8606): (elided one frame from package dart:async)
I/flutter ( 8606): ════════════════════════════════════════════════════════════════════════════════════════════════════
Reloaded 0 of 528 libraries in 4,661ms.

Issue 2:
Steps to Reproduce

Make an app exactly like this sample: https://pub.dartlang.org/packages/camera

Deploy the app to a Huawei Y6 2018 with Android 8.0.0

See this:

Logs

Launching lib\main.dart on ATU L21 in debug mode...
Built build\app\outputs\apk\debug\app-debug.apk.
I/CameraManagerGlobal(30810): Connecting to camera service
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 0
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 1
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 2
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 2
E/BufferQueueProducer(30810): [] Can not get hwsched service
E/BufferQueueProducer(30810): [] Can not get hwsched service
I/PermissionManager(30810): camera remind result:true
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 2
I/CameraManagerGlobal(30810): single back camera, do not need hide aux camera, device number: 2
I/zygote64(30810): Do partial code cache collection, code=27KB, data=27KB
I/zygote64(30810): After code cache collection, code=20KB, data=24KB
I/zygote64(30810): Increasing code cache capacity to 128KB

info - Duplicate import - lib\main.dart:3:8 - duplicate_import
info - Unused import: 'package:fluff/main.dart' - test\widget_test.dart:11:8 - unused_import
error - The constructor returns type 'dynamic' that isn't of expected type 'Widget' - test\widget_test.dart:16:29 -
strong_mode_invalid_cast_new_expr
error - Undefined class 'MyApp' - test\widget_test.dart:16:33 - undefined_class

[√] Flutter (Channel beta, v0.10.2, on Microsoft Windows [Version 10.0.17134.345], locale da-DK)
• Flutter version 0.10.2 at c:\workspace\flutter
• Framework revision d8cbb80206 (3 weeks ago), 2018-10-26 01:30:21 -0400
• Engine revision 6c2ade9fa2
• Dart version 2.1.0-dev.8.0.flutter-bf26f760b1

[√] Android toolchain - develop for Android devices (Android SDK 28.0.3)
• Android SDK at C:\Users\asgerhallas\AppData\Local\Android\sdk
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-28, build-tools 28.0.3
• Java binary at: C:\Program Files\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1136-b06)
• All Android licenses accepted.

[√] Android Studio (version 3.2)
• Android Studio at C:\Program Files\Android\Android Studio
• Flutter plugin version 30.0.1
• Dart plugin version 181.5656
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1136-b06)

[√] VS Code, 64-bit edition (version 1.28.2)
• VS Code at C:\Program Files\Microsoft VS Code
• Flutter extension version 2.20.0

[√] Connected device (1 available)
• ATU L21 • GSM9X18A07G03187 • android-arm64 • Android 8.0.0 (API 26)

• No issues found!