Tests: Added missing check if permissions are supported on the filesystem

Two test methods didnt have the required check for permissions, so they were
not skipped under windows, leading to CI failures.

core/src/main/java/org/elasticsearch/plugins/PluginManager.java

@@ -24,7 +24,6 @@ import org.elasticsearch.*;
 import org.elasticsearch.bootstrap.JarHell;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.cli.Terminal;
-import org.elasticsearch.common.collect.Iterators;
 import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.common.http.client.HttpDownloadHelper;
 import org.elasticsearch.common.io.FileSystemUtils;

core/src/test/java/org/elasticsearch/plugins/PluginManagerPermissionTests.java

@@ -213,6 +213,8 @@ public class PluginManagerPermissionTests extends ESTestCase {
     }
 
     public void testThatConfigDirectoryBeingAFileAbortsInstallationAndDoesNotAccidentallyDeleteThisFile() throws Exception {
+        assumeTrue("File system does not support permissions, skipping", supportsPermissions);
+
         Files.createDirectories(environment.configFile());
         Files.createFile(environment.configFile().resolve(pluginName));
         URL pluginUrl = createPlugin(randomBoolean(), true);
@@ -230,6 +232,8 @@ public class PluginManagerPermissionTests extends ESTestCase {
     }
 
     public void testThatBinDirectoryBeingAFileAbortsInstallationAndDoesNotAccidentallyDeleteThisFile() throws Exception {
+        assumeTrue("File system does not support permissions, skipping", supportsPermissions);
+
         Files.createDirectories(environment.binFile());
         Files.createFile(environment.binFile().resolve(pluginName));
         URL pluginUrl = createPlugin(true, randomBoolean());