V8 Buildbot: Don't close tree for known isolate timeouts on windows.
V8 Buildbot: Don't close tree for known isolate timeouts on windows.

Follow up after https://codereview.chromium.org/1626263002

We now have the same problem on win32 since the slaves use
the Win7 pool.

BUG=535160
TBR=tandrii@chromium.org, kjellander@chromium.org

Review URL: https://codereview.chromium.org/1684343003

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@298736 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build