Breaking on exceptions while being in widget inspector mode catches widget inspector exceptions

How to reproduce:

- In Inspector page, enable widget inspection
- In Debugger page, select "All exceptions" to pause on all exceptions
- Select a widget in the app
- Go back to Inspector page
- You will see "Main isolate is paused in the debugger"
- Go back to Debugger page
- See that you are paused on an exception from `widget_inspector`

Ways to fix:
- When pausing on exceptions, ignore exceptions with `widget_inspector` in the stacktrace if in widget inspector mode
- Disable breakpoints during widget inspection
- Other ways?

在启用 widget inspection 并选中““All exceptions””的情况下，在 Inspector 和 Debugger 页面上复现该工作流。跟踪堆栈跟踪中包含 `widget_inspector` 的异常如何到达暂停行为；完成的标准是 widget-inspector 异常不再中断检查，而普通异常仍然会暂停。

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