Add support for rendering PDF combobox form control for <select> element

[nkahoang]

Add support for rendering PDF form ComboBox from element (also pull-requested to wkhtmltopdf/qt project)
Include JetBrain IDE's .idea folder into .gitignore

[Nowaker]

@nkahoang FYI: putting your local environment specific directories into gitignore isn't considered a good practise. https://stackoverflow.com/questions/6626136/best-practice-for-adding-gitignore-to-repo

[nkahoang]

Hi I reversed the .gitignore file and also added support for HiddenField (useful for tagging PDF document then read it again using PdfTk, for example). Qt repo is also updated correspondingly. Please let me know if you need anything else to merge my pull request

[ansata2001]

@nkahoang It doesn't compile, I've cloned your repo and merged it with the latest master from origin and getting this:

../../../qt/include/QtGui/../../../../../qt/src/gui/painting/qpainter.h:458:10: note:   candidate expects 7 arguments, 8 provided
/home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:855:54: error: no matching function for call to 'QPainter::addCheckBox(QRectF, QMap<QString, QString>&, bool, QString&, bool)'
     elm.evaluateJavaScript("this.readonly;").toBool());
                                                      ^
/home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:855:54: note: candidate is:
In file included from ../../../qt/include/QtGui/qpainter.h:1:0,
                 from ../../../qt/include/QtGui/QPainter:1,
                 from /home/vagrant/wkhtmltopdf/src/lib/pdfconverter_p.hh:33,
                 from /home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:22:
../../../qt/include/QtGui/../../../../../qt/src/gui/painting/qpainter.h:459:10: note: void QPainter::addCheckBox(const QRectF&, bool, const QString&, bool)
     void addCheckBox(const QRectF &r, bool checked=false, const QString &name="", bool readOnly=false);
          ^
../../../qt/include/QtGui/../../../../../qt/src/gui/painting/qpainter.h:459:10: note:   candidate expects 4 arguments, 5 provided
/home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:857:22: error: 'class QPainter' has no member named 'addHiddenField'
             painter->addHiddenField(
                      ^
/home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:879:22: error: 'class QPainter' has no member named 'addComboBox'
             painter->addComboBox(
                      ^
/home/vagrant/wkhtmltopdf/src/lib/pdfconverter.cc:890:26: error: 'class QPainter' has no member named 'addPageJavaScript'
                 painter->addPageJavaScript(

[ashkulz]

You'll need to merge the changes in the Qt repo as well.

[ansata2001]

@ashkulz I tried to compile it with QT pointing to 82b568bd2e1dfb as in @nkahoang repo and with QT pointing to ccffd0 with same result as above.

[ashkulz]

Sorry, this is not on my priority list of merging/investigation as I am trying to upgrade to Qt5 -- I will consider this afterwards, as this will obviously have to be reimplemented there.

[epabst]

This change looks unintentional.