Remove spurious base/debug/stack_trace.h include in WebPluginContainerImpl
Remove spurious base/debug/stack_trace.h include in WebPluginContainerImpl

This seems to have been a debugging mistake from
https://src.chromium.org/viewvc/blink?view=rev&revision=193668

Review URL: https://codereview.chromium.org/1221303018

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@198472 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