Remove some useless codes in tpview

Remove some useless codes in tpview

BUG=None
TEST=Run tpview in the chrome browser

Change-Id: Ic6330783c112c2a7953dac193c8c3d6094518ee4
Reviewed-on: https://gerrit.chromium.org/gerrit/29869
Reviewed-by: Andrew de los Reyes <adlr@chromium.org>
Commit-Ready: KuanYu Chu <chuwfuny@chromium.org>
Tested-by: KuanYu Chu <chuwfuny@chromium.org>