Core: Delay coreOpened signal emission
Core: Delay coreOpened signal emission

This prevents some window restoring flickering.

Change-Id: Iead0e0f2129b969e1de7e22dbf15e641740e40e1
Reviewed-by: Orgad Shaneh <2b010cbad792a0c0a8175f752f93f83941fc6bc1@gmail.com>
Reviewed-by: Eike Ziller <c142da16c73a95a82d35191bcc55b22835617128@digia.com>

AltarBeastiful/qt-creator,xianian/qt-creator,kuba1/qtcreator,AltarBeastiful/qt-creator,xianian/qt-creator,xianian/qt-creator,colede/qtcreator,danimo/qt-creator,amyvmiwei/qt-creator,omniacreator/qtcreator,AltarBeastiful/qt-creator,kuba1/qtcreator,xianian/qt-creator,maui-packages/qt-creator,darksylinc/qt-creator,farseerri/git_code,colede/qtcreator,AltarBeastiful/qt-creator,darksylinc/qt-creator,martyone/sailfish-qtcreator,AltarBeastiful/qt-creator,darksylinc/qt-creator,kuba1/qtcreator,maui-packages/qt-creator,kuba1/qtcreator,Distrotech/qtcreator,AltarBeastiful/qt-creator,omniacreator/qtcreator,colede/qtcreator,amyvmiwei/qt-creator,colede/qtcreator,farseerri/git_code,kuba1/qtcreator,maui-packages/qt-creator,farseerri/git_code,Distrotech/qtcreator,amyvmiwei/qt-creator,omniacreator/qtcreator,amyvmiwei/qt-creator,darksylinc/qt-creator,danimo/qt-creator,colede/qtcreator,kuba1/qtcreator,martyone/sailfish-qtcreator,omniacreator/qtcreator,kuba1/qtcreator,maui-packages/qt-creator,danimo/qt-creator,amyvmiwei/qt-creator,darksylinc/qt-creator,Distrotech/qtcreator,maui-packages/qt-creator,omniacreator/qtcreator,amyvmiwei/qt-creator,colede/qtcreator,darksylinc/qt-creator,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,farseerri/git_code,AltarBeastiful/qt-creator,martyone/sailfish-qtcreator,omniacreator/qtcreator,darksylinc/qt-creator,martyone/sailfish-qtcreator,xianian/qt-creator,martyone/sailfish-qtcreator,martyone/sailfish-qtcreator,colede/qtcreator,kuba1/qtcreator,danimo/qt-creator,Distrotech/qtcreator,kuba1/qtcreator,danimo/qt-creator,danimo/qt-creator,xianian/qt-creator,amyvmiwei/qt-creator,farseerri/git_code,maui-packages/qt-creator,farseerri/git_code,martyone/sailfish-qtcreator,maui-packages/qt-creator,farseerri/git_code,Distrotech/qtcreator,danimo/qt-creator,omniacreator/qtcreator,danimo/qt-creator,xianian/qt-creator,Distrotech/qtcreator,danimo/qt-creator,Distrotech/qtcreator,xianian/qt-creator,darksylinc/qt-creator,amyvmiwei/qt-creator,farseerri/git_code