Remove unused includes

We eventually want to get rid of GtkSelectionData.
As a first step, stop including gtkselection.h unnecessarily.

gtk/gtkdragsource.h

@@ -31,7 +31,6 @@
 #error "Only <gtk/gtk.h> can be included directly."
 #endif
 
-#include <gtk/gtkselection.h>
 #include <gtk/gtkwidget.h>
 
 

gtk/gtkentry.c

@@ -53,7 +53,6 @@
 #include "gtkpopover.h"
 #include "gtkprivate.h"
 #include "gtkprogressbar.h"
-#include "gtkselection.h"
 #include "gtksettings.h"
 #include "gtksnapshot.h"
 #include "gtkstylecontextprivate.h"

gtk/gtkentry.h

@@ -39,7 +39,6 @@
 #include <gtk/gtkentrybuffer.h>
 #include <gtk/gtkentrycompletion.h>
 #include <gtk/gtkimage.h>
-#include <gtk/gtkselection.h>
 
 
 G_BEGIN_DECLS

gtk/gtkiconview.h

@@ -26,7 +26,6 @@
 #include <gtk/gtktreemodel.h>
 #include <gtk/gtkcellrenderer.h>
 #include <gtk/gtkcellarea.h>
-#include <gtk/gtkselection.h>
 #include <gtk/gtktooltip.h>
 #include <gtk/gtkdragsource.h>
 #include <gtk/gtkdragdest.h>

gtk/gtksidebarrow.c

@@ -26,7 +26,6 @@
 #include "gtklabel.h"
 #include "gtkstylecontext.h"
 #include "gtkrevealer.h"
-#include "gtkselection.h"
 #include "gtkintl.h"
 #include "gtkspinner.h"
 

gtk/gtktext.c

@@ -50,7 +50,6 @@
 #include "gtkpango.h"
 #include "gtkpopovermenu.h"
 #include "gtkprivate.h"
-#include "gtkselection.h"
 #include "gtksettings.h"
 #include "gtksnapshot.h"
 #include "gtkstylecontextprivate.h"

gtk/gtkwidget.c

@@ -57,7 +57,6 @@
 #include "gtkrootprivate.h"
 #include "gtknativeprivate.h"
 #include "gtkscrollable.h"
-#include "gtkselection.h"
 #include "gtksettingsprivate.h"
 #include "gtksizegroup-private.h"
 #include "gtksnapshotprivate.h"