flutter / flutter/devtools

DevTools sample rate is incorrect.

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P2 screen: cpu profiler
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Description

### Steps to reproduce

1. Open Devtools
2. Connect to an App
3. Select the CPU profiler tab
4. Set the cpu sampling rate to high
5. Record some data
6. Once the data is recorded, note the smallest available sample, which reveals how often the stack is sampled
7. Look at the bottom of the graph, where the supposed sample rate is stored

### Expected results

The minimum possible sample would be 0.05 milliseconds
The number of samples taken would be the sample's length divided by the sample rate.

### Actual results

The minimum possible sample is variable, lowest I saw was 0.9ms
There are sometimes only a few dozen samples when doing multi-second recordings.

![image](https://github.com/flutter/flutter/assets/3525610/d6419638-f5d3-455d-b5b4-36a6039efd82)

### Code sample

Not necessary.

### Screenshots or Video

Screenshots / Video demonstration

[Youtube upload, because github doesn't like MKV](https://youtu.be/H41i-UdTRhE)

### Logs

_No response_

### Flutter Doctor output

Doctor output

```console
PS C:\Users\Hidden> flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.16.8, on Microsoft Windows [Version 10.0.22631.3085], locale en-BE)
[✓] Windows Version (Installed version of Windows is version 10 or higher)
[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.2)
[✓] Chrome - develop for the web
[✓] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.7.6)
[✓] Android Studio (version 2022.2)
[✓] VS Code (version 1.85.2)
[✓] Connected device (4 available)
[✓] Network resources

• No issues found!
```

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