[Swarming] Isolate jsfunfuzz.

tools/jsfunfuzz/jsfunfuzz.isolate

 # Copyright 2016 the V8 project authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 {
   'variables': {
     'command': [
-      'check-static-initializers.sh',
+      'fuzz-harness.sh',
     ],
     'files': [
-      'check-static-initializers.sh',
+      # Grab current directory. This avoids adding logic for checking the
+      # existence of the jsfunfuzz subdirectory.
+      './',
     ],
   },
   'includes': [
-    '../src/d8.isolate',
+    '../../src/d8.isolate',
   ],
 }