[sip] add missing ConvertToClassCode

This was causing an issue if you tried to access widgets in a form using findChildren
widgets could not be casted to QGIs native types

also sipify QgsFilterLineEdit and QgsRelationEditorWidget

python/auto_sip.blacklist

@@ -282,7 +282,6 @@ gui/qgsfeatureselectiondlg.sip
 gui/qgsfieldvalidator.sip
 gui/qgsfieldvalueslineedit.sip
 gui/qgsfiledropedit.sip
-gui/qgsfilterlineedit.sip
 gui/qgsfloatingwidget.sip
 gui/qgsfocuswatcher.sip
 gui/qgsformannotation.sip
@@ -346,7 +345,6 @@ gui/qgsquerybuilder.sip
 gui/qgsrasterformatsaveoptionswidget.sip
 gui/qgsrasterlayersaveasdialog.sip
 gui/qgsrasterpyramidsoptionswidget.sip
-gui/qgsrelationeditorwidget.sip
 gui/qgsrubberband.sip
 gui/qgsscalerangewidget.sip
 gui/qgsscalevisibilitydialog.sip

python/gui/editorwidgets/qgsdoublespinbox.sip

@@ -9,6 +9,15 @@
 
 
 
+
+%ModuleHeaderCode
+// fix to allow compilation with sip that for some reason
+// doesn't add this include to the file where the code from
+// ConvertToSubClassCode goes.
+#include <qgsdoublespinbox.h>
+%End
+
+
 class QgsDoubleSpinBox : QDoubleSpinBox
 {
 %Docstring
@@ -19,6 +28,13 @@ class QgsDoubleSpinBox : QDoubleSpinBox
 
 %TypeHeaderCode
 #include "qgsdoublespinbox.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsDoubleSpinBox *>( sipCpp ) )
+      sipType = sipType_QgsDoubleSpinBox;
+    else
+      sipType = NULL;
 %End
   public:
 

python/gui/editorwidgets/qgsrelationreferencewidget.sip

@@ -10,11 +10,25 @@
 
 
 
+%ModuleHeaderCode
+// fix to allow compilation with sip that for some reason
+// doesn't add this include to the file where the code from
+// ConvertToSubClassCode goes.
+#include <qgsrelationreferencewidget.h>
+%End
+
 class QgsRelationReferenceWidget : QWidget
 {
 
 %TypeHeaderCode
 #include "qgsrelationreferencewidget.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsRelationReferenceWidget *>( sipCpp ) )
+      sipType = sipType_QgsRelationReferenceWidget;
+    else
+      sipType = NULL;
 %End
   public:
 

python/gui/editorwidgets/qgsspinbox.sip

@@ -9,6 +9,15 @@
 
 
 
+
+%ModuleHeaderCode
+// fix to allow compilation with sip 4.7 that for some reason
+// doesn't add this include to the file where the code from
+// ConvertToSubClassCode goes.
+#include <qgsspinbox.h>
+%End
+
+
 class QgsSpinBox : QSpinBox
 {
 %Docstring
@@ -19,6 +28,13 @@ class QgsSpinBox : QSpinBox
 
 %TypeHeaderCode
 #include "qgsspinbox.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsSpinBox *>( sipCpp ) )
+      sipType = sipType_QgsSpinBox;
+    else
+      sipType = NULL;
 %End
   public:
 

python/gui/qgscolorbutton.sip

@@ -19,6 +19,13 @@ class QgsColorButton : QToolButton
 
 %TypeHeaderCode
 #include "qgscolorbutton.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsColorButton *>( sipCpp ) )
+      sipType = sipType_QgsColorButton;
+    else
+      sipType = NULL;
 %End
   public:
 

python/gui/qgsexternalresourcewidget.sip

@@ -11,6 +11,14 @@
 
 
 
+%ModuleHeaderCode
+// fix to allow compilation with sip that for some reason
+// doesn't add this include to the file where the code from
+// ConvertToSubClassCode goes.
+#include <qgsexternalresourcewidget.h>
+%End
+
+
 class QgsExternalResourceWidget : QWidget
 {
 %Docstring
@@ -21,6 +29,13 @@ class QgsExternalResourceWidget : QWidget
 
 %TypeHeaderCode
 #include "qgsexternalresourcewidget.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsExternalResourceWidget *>( sipCpp ) )
+      sipType = sipType_QgsExternalResourceWidget;
+    else
+      sipType = NULL;
 %End
   public:
     enum DocumentViewerContent

python/gui/qgsfilewidget.sip

@@ -19,6 +19,13 @@ class QgsFileWidget : QWidget
 
 %TypeHeaderCode
 #include "qgsfilewidget.h"
+%End
+
+%ConvertToSubClassCode
+    if ( qobject_cast<QgsFileWidget *>( sipCpp ) )
+      sipType = sipType_QgsFileWidget;
+    else
+      sipType = NULL;
 %End
   public: