[starter eel] AT-1851 Simplify a bit multi-routing file system flag p…

…ropagation

GitOrigin-RevId: 0be6c090af8011dae483e49c63a6c1d99390af8c

intellij.tools.ide.starter/src/com/intellij/ide/starter/models/VMOptions.kt

@@ -350,12 +350,11 @@ data class VMOptions(
   /** Option should be removed when https://youtrack.jetbrains.com/issue/IJPL-160621/Enable-MultiRoutingFileSystem-for-all-OS-and-all-IDEs is completed */
   @Suppress("unused")
   fun enableMultiRoutingFileSystem() {
-    // temporary hack: only specific tests which are ready, should enable it
-    if (System.getenv("ENABLE_MULTI_ROUTING_FILE_SYSTEM") != "true") {
-      logOutput("Multi-routing file system is disabled in tests")
-      return
+    // if tests were starter with multi-routing FS flag - just propagate it to the IDE
+    if (System.getProperty("java.nio.file.spi.DefaultFileSystemProvider")?.trim() == "com.intellij.platform.core.nio.fs.MultiRoutingFileSystemProvider") {
+      addSystemProperty("java.nio.file.spi.DefaultFileSystemProvider", "com.intellij.platform.core.nio.fs.MultiRoutingFileSystemProvider")
     }
-    addSystemProperty("java.nio.file.spi.DefaultFileSystemProvider", "com.intellij.platform.core.nio.fs.MultiRoutingFileSystemProvider")
+    else logOutput("Multi-routing file system is disabled in tests")
   }
 
   /**