Always clear traffic shaping regardless of whether it was started.
Always clear traffic shaping regardless of whether it was started.

This prevents bugs where a previous run didn't shut down properly
and traffic shaping remains in place.

Review URL: http://codereview.chromium.org/6541032

git-svn-id: abd770af2affaf62930f25b244f6edafe8ddae5b@319 164481a5-15cb-f69f-4b93-856c5b7754c5

colin-scott/web-page-replay,andrey-malets/web-page-replay,chromium/web-page-replay,ting-yuan/web-page-replay,bpsinc-native/src_third_party_webpagereplay,snorp/web-page-replay,bpsinc-native/src_third_party_webpagereplay,snorp/web-page-replay,andrey-malets/web-page-replay,colin-scott/web-page-replay,chromium/web-page-replay,bpsinc-native/src_third_party_webpagereplay,ting-yuan/web-page-replay