Remove experimental attempt at FAT detection

We'll just have to address each instance individually.

src/ProjectFileIO.cpp

@@ -326,11 +326,6 @@ bool ProjectFileIO::OpenConnection(FilePath fileName /* = {}  */)
       }
    }
 
-   if (FileNames::FATFilesystemDenied(fileName, XO("Project resides on FAT formatted drive.")))
-   {
-      return false;
-   }
-
    // Pass weak_ptr to project into DBConnection constructor
    curConn = std::make_unique<DBConnection>(
       mProject.shared_from_this(), mpErrors, [this]{ OnCheckpointFailure(); } );

src/ProjectFileManager.cpp

@@ -858,6 +858,13 @@ void ProjectFileManager::OpenFile(const FilePath &fileNameArg, bool addtohistory
    auto fileName = PlatformCompatibility::ConvertSlashInFileName(
       PlatformCompatibility::GetLongFileName(fileNameArg));
 
+   if (FileNames::FATFilesystemDenied(fileName,
+                                      XO("Project resides on FAT formatted drive.\n"
+                                         "Copy it to another drive to open it.")))
+   {
+      return;
+   }
+
    // Make sure it isn't already open.
    // Vaughan, 2011-03-25: This was done previously in AudacityProject::OpenFiles()
    //    and AudacityApp::MRUOpen(), but if you open an aup file by double-clicking it