Add the missing Blocker call for `chmod`.

PiperOrigin-RevId: 628085642
Change-Id: I7a1286606c55297548262e922aafc73668a4948c
diff --git a/src/main/java/com/google/devtools/build/lib/unix/UnixFileSystem.java b/src/main/java/com/google/devtools/build/lib/unix/UnixFileSystem.java
index 2e95d65..8e733e5 100644
--- a/src/main/java/com/google/devtools/build/lib/unix/UnixFileSystem.java
+++ b/src/main/java/com/google/devtools/build/lib/unix/UnixFileSystem.java
@@ -323,7 +323,12 @@
 
   @Override
   protected void chmod(PathFragment path, int mode) throws IOException {
-    NativePosixFiles.chmod(path.toString(), mode);
+    long comp = Blocker.begin();
+    try {
+      NativePosixFiles.chmod(path.toString(), mode);
+    } finally {
+      Blocker.end(comp);
+    }
   }
 
   @Override