Issue 1:
Steps to Reproduce

flutter run --preview-dart-2

Make any tiny tweak to widget_inspector.dart or any other file in package:flutter

Trigger hot reload

See the warning:

Some program elements were changed during reload but did not run when the view was reassembled;
you may need to restart the app (by pressing "R") for the changes to have an effect.
• _RenderSliverPersistentHeaderForWidgetsMixin.handleEvent (package:flutter/src/widgets/sliver_persistent_header.dart:253)
• #errors (file:///)
• #errors (file:///)
• _RenderSliverPinnedPersistentHeader.handleEvent (package:flutter/src/widgets/sliver_persistent_header.dart:309)

Issue 2:
Steps to Reproduce

I was working through the Write Your First App tutorial. I received warnings that some program elements didn't run when the view was reassembled, but the UI seemed to be updated correctly.

For example, when I changed my code from step 2 to step 3, I received the following message:

Performing hot reload...
Reloaded 1 of 430 libraries in 627ms.

Some program elements were changed during reload but did not run when the view was reassembled;
you may need to restart the app for the changes to have an effect.
• RandomWordsState.didUpdateWidget (lib/main.dart:28)
• RandomWordsState._widget= (lib/main.dart:28)

In addition to the UI appeared to be fine, I didn't know how relevant RandomWordsState.didUpdateWidget and RandomWordsState._widget were to me, since these two methods were not actually in the code I wrote.

Then, when I changed my code from step 3 to step 4, I got the following message:

Initializing hot reload...
Reloaded 1 of 430 libraries in 915ms.

Some program elements were changed during reload but did not run when the view was reassembled;
you may need to restart the app for the changes to have an effect.
• RandomWordsState._suggestions (lib/main.dart:22)
• RandomWordsState._biggerFont (lib/main.dart:24)

Again, the UI seemed to be functioning correctly, including the font size, which the message says the relevant code didn't run.

Flutter Doctor

[✓] Flutter (Channel master, v0.2.9-pre.9, on Mac OS X 10.13.3 17D102, locale en-US)
• Flutter version 0.2.9-pre.9 at /Users/taodong/Code/flutter_repos/flutter
• Framework revision 5e9424419e (35 minutes ago), 2018-04-03 10:35:07 -0700
• Engine revision 04f3c6557c
• Dart version 2.0.0-dev.43.0.flutter-52afcba357

[!] Android toolchain - develop for Android devices (Android SDK 27.0.0)
• Android SDK at /Users/taodong/Library/Android/sdk
• Android NDK location not configured (optional; useful for native profiling support)
• Platform android-27, build-tools 27.0.0
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)
✗ Android license status unknown.

[✓] iOS toolchain - develop for iOS devices (Xcode 9.2)
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 9.2, Build version 9C40b
• ios-deploy 1.9.2
• CocoaPods version 1.4.0

[✓] Android Studio (version 3.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b01)

[✓] IntelliJ IDEA Community Edition (version 2018.1)
• IntelliJ at /Applications/IntelliJ IDEA CE.app
• Flutter plugin installed
• Dart plugin version 181.4203.498

[✓] VS Code (version 1.20.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Dart Code extension version 2.9.0

[✓] Connected devices (1 available)
• iPhone SE • AD00445E-9D4A-454D-892F-1419FF77D3A1 • ios • iOS 11.2 (simulator)

! Doctor found issues in 1 category.

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