Browser Tester: increased the timeout for loading nexes.
Browser Tester: increased the timeout for loading nexes.

A spurious timeout was observed on the bots.

BUG= none
TEST= ./scons chrome_browser_tests

Review URL: http://codereview.chromium.org/6610027

git-svn-id: 721b910a23eff8a86f00c8fd261a7587cddf18f8@4452 fcba33aa-ac0c-11dd-b9e7-8d5594d729c2

nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,nacl-webkit/native_client,sbc100/native_client,nacl-webkit/native_client,nacl-webkit/native_client,sbc100/native_client,sbc100/native_client,sbc100/native_client