Set m_completelyLoaded to false when m_networkState is set to NETWORK_LOADING.
Set m_completelyLoaded to false when m_networkState is set to NETWORK_LOADING.

BUG=519060

Review URL: https://codereview.chromium.org/1284613004

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@200471 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk