Only add pdb to isolate when fastbuild!=2.

chrome/unit_tests.isolate

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 {
   'conditions': [
     ['OS=="android" or OS=="linux"', {
       'variables': {
         'isolate_dependency_untracked': [
           '<(PRODUCT_DIR)/test_data/',
         ],
@@ skipping 97 matching lines @@
           '<(PRODUCT_DIR)/libexif.dll',
           '<(PRODUCT_DIR)/osmesa.dll',
           '<(PRODUCT_DIR)/verifier_test_dll_1.dll',
           '<(PRODUCT_DIR)/verifier_test_dll_2.dll',
           'test/data/safe_browsing/signed_binary.dll',
         ],
         'isolate_dependency_untracked': [
           '../ppapi/lib/gl/include/KHR/',
           '../skia/ext/data/',
           '../ui/base/glib/',
+        ],
+      },
+    }],
+    ['OS=="win" and (fastbuild==0 or fastbuild==1)', {
+      'variables': {
+        'isolate_dependency_untracked': [
           '<(PRODUCT_DIR)/unit_tests.exe.pdb',
         ],
       },
     }],
     ['chromeos==1', {
       'variables': {
         'isolate_dependency_tracked': [
           '<(PRODUCT_DIR)/libexif.so',
         ],
         'isolate_dependency_untracked': [
           '../chromeos/test/data/network/',
         ],
       },
     }],
   ],
   'includes': [
     '../base/base.isolate',
   ],
 }