[Qt][WK2] Fold QtWebPageLoadClient into QQuickWebViewPrivate and move to C API.
https://bugs.webkit.org/show_bug.cgi?id=108473

Reviewed by Simon Hausmann.
Signed off for WebKit2 by Benjamin Poulain.

This patch removes the QtWebPageLoadClient and moves the functionality into the
QQuickWebViewPrivate as most callback methods are calling the private webview
indirectly anyway.

The patch also moves as much of the functionality to the C API as is possible with
the current C API.

* Target.pri:
* UIProcess/API/qt/qquickwebview.cpp:
(QQuickWebViewPrivate::initialize):
(QQuickWebViewPrivate::didStartProvisionalLoadForFrame):
(QQuickWebViewPrivate::didReceiveServerRedirectForProvisionalLoadForFrame):
(QQuickWebViewPrivate::didFailLoad):
(QQuickWebViewPrivate::didCommitLoadForFrame):
(QQuickWebViewPrivate::didFinishLoadForFrame):
(QQuickWebViewPrivate::didSameDocumentNavigationForFrame):
(QQuickWebViewPrivate::didReceiveTitleForFrame):
(QQuickWebViewPrivate::didStartProgress):
(QQuickWebViewPrivate::didChangeProgress):
(QQuickWebViewPrivate::didFinishProgress):
(QQuickWebViewPrivate::didChangeBackForwardList):
(QQuickWebViewPrivate::setTransparentBackground):
(QQuickWebViewPrivate::transparentBackground):
(QQuickWebViewPrivate::loadProgressDidChange):
* UIProcess/API/qt/qquickwebview_p.h:
(WebKit):
* UIProcess/API/qt/qquickwebview_p_p.h:
(WebKit):
(QQuickWebViewPrivate):
* UIProcess/qt/QtWebError.cpp:
(WebKit::QtWebError::url):
* UIProcess/qt/QtWebPageLoadClient.cpp: Removed.
* UIProcess/qt/QtWebPageLoadClient.h: Removed.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@142095 268f45cc-cd09-0410-ab3c-d52691b4dbfc