Discovered while investigating #137168. As of writing this, I believe that resolving this issue is prerequisite to solving that one.

Consider #137168. The crashing exception here is PathNotFoundException: PathNotFoundException: Deletion failed, path = 'D:\<project dir path>\windows\flutter\ephemeral\.plugin_symlinks' (OS Error: The system cannot find the path specified. , errno = 3). However, if we look at the code that threw this, we notice that it confirms the existence of the directory before it tries to delete it.

Barring some more complex bug in the tool or Dart's filesystem abstractions, this strongly suggests that something happened to this directory in the time between the tool checking for its existence and trying to delete it.

While it could be argued that this deleteSync call should be replaced a ErrorHandlingFileSystem.deleteIfExists call, this still would not be sufficient to prevent the crash, because deleteIfExists will still throw if it encounters ERROR_PATH_NOT_FOUND:

Notice that if the error code is not kSystemCannotFindFile, we will rethrow. Here is the definition of this constant:

We should augment deleteIfExists to not rethrow in the presence of ERROR_PATH_NOT_FOUND on Windows.