Repository: flutter
Issue: Failed to xcodebuild against multiple iOS devices: Build service could not start build operation: unknown error while handling message: Could not acquire lock at path `Path(str: ".../DerivedData/.../...-Workspace.lock")`
Labels: platform-ios,tool,P3,team-ios,triaged-ios

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I'm trying to debugging my application with iPhone and iPad simulators. But, application only launched on one simulator.

## Steps to Reproduce

<!-- Please tell us exactly how to reproduce the problem you are running into. -->
This is my `launch.json`

```
{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Current Device",
            "request": "launch",
            "type": "dart"
        },
        {
            "name": "iPhone 11",
            "request": "launch",
            "type": "dart",
            "deviceId": "iPhone 11"
        },
        {
            "name": "iPad",
            "request": "launch",
            "type": "dart",
            "deviceId": "iPad"
        }
    ],
    "compounds": [
        {
            "name": "iOS",
            "configurations": [
                "iPhone 11",
                "iPad"
            ]
        }
    ]
}
```

## Logs

<!--
      Include the full logs of the commands you are running between the lines
      with the backticks below. If you are running any "flutter" commands,
      please include the output of running them with "--verbose"; for example,
      the output of running "flutter --verbose create foo".
-->

```
Launching lib/main.dart on iPhone 11 in debug mode...
Xcode build done.                                            1.9s
Failed to build iOS app
Error output from Xcode build:
↳
    ** BUILD FAILED **
Xcode's output:
↳
    note: Using new build system
    error: Build service could not start build operation: unknown error while handling message: Could not acquire lock at path `Path(str: "/Users/ekasetiawans/Library/Developer/Xcode/DerivedData/Runner-cvnxrdslexqanxgifauwqwadpzrb/Build/Intermediates.noindex/XCBuildData/PIFCache/WORKSPACE@v11_mod=1579070672.0_hash=6162b33aa8199599d972cf41ab25bc47_subobjects=B549A30C3B2425E52674E89430410CE0-Workspace.lock")`
Could not build the application for the simulator.
Error launching application on iPhone 11.
Exited (sigterm)
```

<!-- If possible, paste the output of running `flutter doctor -v` here. -->

```
```