Exclude shell_nacl_browser_delegate_unittest.cc on disable_nacl configuration

NOTRY=true

Review URL: https://codereview.chromium.org/491723002

Cr-Commit-Position: refs/heads/master@{#290751}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290751 0039d316-1c4b-4281-b951-d872f2087c98

extensions/shell/app_shell.gyp

@@ -200,6 +200,13 @@
         '../test/extensions_unittests_main.cc',
         'browser/shell_nacl_browser_delegate_unittest.cc',
       ],
+      'conditions': [
+        ['disable_nacl==1', {
+          'sources!': [
+            'browser/shell_nacl_browser_delegate_unittest.cc',
+          ],
+        }],
+      ],
     },
     {
       'target_name': 'app_shell_version_header',