Fixes: Pressing return in search panel didn't run the search.

It did so only if the focus was on the search term line edit.

Task-number: QTCREATORBUG-6114
Change-Id: I0cf051ed0f5f4e7403d7c36eb2173a71de370276
Reviewed-on: http://codereview.qt-project.org/5252


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Leandro T. C. Melo <leandro.melo@nokia.com>