Our current top crasher is an unclear error when ProcessManager fails to resolve an executable path. To fix this, we'd like to being adjusting the process resolution logic and adding more instrumentation to track failures. In order to begin the process, the ProcessManager has been folded back into the flutter tool
Integration tests must only go through the real file system/process manager/platform. The global indirection makes this code harder to understand than if it directly referred to the concrete instances that are being used.
Update the integration shard to use a const instance of a LocalFIleSystem, LocalProcessManager, and LocalPlatform. Remove global usage and apply testWithoutContext.
