[Qt] Zoom in to the focused node only when vkb starts becoming visible https://bugs...

[Qt] Zoom in to the focused node only when vkb starts becoming visible https://bugs.webkit.org/show_bug.cgi?id=76174

Reviewed by Simon Hausmann.

Remove the old code which always zoomed in when something got focus,
even via JavaScript, and replaced it with code checking the state of
the Qt input panel.

Also make sure that we do not zoom in or request the input panel if
the item is not focused.

* UIProcess/PageClient.h:
* UIProcess/WebPageProxy.cpp:
* UIProcess/WebPageProxy.h:
* UIProcess/WebPageProxy.messages.in:
* UIProcess/qt/QtPageClient.cpp:
* UIProcess/qt/QtPageClient.h:
* UIProcess/qt/QtWebPageEventHandler.cpp:
(QtWebPageEventHandler::QtWebPageEventHandler):
(QtWebPageEventHandler::~QtWebPageEventHandler):
(QtWebPageEventHandler::inputPanelVisibleChanged):
* UIProcess/qt/QtWebPageEventHandler.h:
* WebProcess/WebCoreSupport/WebEditorClient.cpp:
(WebKit::WebEditorClient::respondToChangedSelection):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@105275 268f45cc-cd09-0410-ab3c-d52691b4dbfc