Revert "iconhelper: Don't check states"

This reverts commit 63f59dde3a.

It turns out, the state was not just necessary for style computation,
but also for tracking RTL and LTR. And so it broke the reftests.

gtk/gtkiconhelper.c

@@ -47,10 +47,12 @@ struct _GtkIconHelperPrivate {
   guint force_scale_pixbuf : 1;
 
   GdkPixbuf *rendered_pixbuf;
+  GtkStateFlags last_rendered_state;
 
   cairo_surface_t *rendered_surface;
   gint rendered_surface_width;
   gint rendered_surface_height;
+  GtkStateFlags last_surface_state;
   gint last_surface_scale;
 };
 
@@ -79,6 +81,8 @@ _gtk_icon_helper_clear (GtkIconHelper *self)
 
   self->priv->storage_type = GTK_IMAGE_EMPTY;
   self->priv->icon_size = GTK_ICON_SIZE_INVALID;
+  self->priv->last_rendered_state = GTK_STATE_FLAG_NORMAL;
+  self->priv->last_surface_state = GTK_STATE_FLAG_NORMAL;
   self->priv->last_surface_scale = 0;
   self->priv->orig_pixbuf_scale = 1;
 }
@@ -132,6 +136,7 @@ _gtk_icon_helper_init (GtkIconHelper *self)
   self->priv->storage_type = GTK_IMAGE_EMPTY;
   self->priv->icon_size = GTK_ICON_SIZE_INVALID;
   self->priv->pixel_size = -1;
+  self->priv->last_rendered_state = GTK_STATE_FLAG_NORMAL;
   self->priv->orig_pixbuf_scale = 1;
 }
 
@@ -236,6 +241,24 @@ ensure_stated_icon_from_info (GtkIconHelper *self,
   return destination;
 }
 
+static gboolean
+check_invalidate_pixbuf (GtkIconHelper *self,
+                         GtkStyleContext *context)
+{
+  GtkStateFlags state;
+
+  state = gtk_style_context_get_state (context);
+
+  if ((self->priv->rendered_pixbuf != NULL) &&
+      (self->priv->last_rendered_state == state))
+    return FALSE;
+
+  self->priv->last_rendered_state = state;
+  g_clear_object (&self->priv->rendered_pixbuf);
+
+  return TRUE;
+}
+
 static GtkIconLookupFlags
 get_icon_lookup_flags (GtkIconHelper *self, GtkStyleContext *context)
 {
@@ -285,7 +308,7 @@ ensure_pixbuf_for_gicon (GtkIconHelper *self,
   GtkIconInfo *info;
   GtkIconLookupFlags flags;
 
-  if (self->priv->rendered_pixbuf)
+  if (!check_invalidate_pixbuf (self, context))
     return;
 
   icon_theme = gtk_icon_theme_get_for_screen (gtk_style_context_get_screen (context));
@@ -316,7 +339,7 @@ ensure_pixbuf_for_icon_set (GtkIconHelper *self,
                             GtkStyleContext *context,
                             GtkIconSet *icon_set)
 {
-  if (self->priv->rendered_pixbuf)
+  if (!check_invalidate_pixbuf (self, context))
     return;
 
   G_GNUC_BEGIN_IGNORE_DEPRECATIONS;
@@ -358,6 +381,10 @@ ensure_pixbuf_from_surface (GtkIconHelper   *self,
   gint width, height;
   cairo_t *cr;
 
+
+  if (!check_invalidate_pixbuf (self, context))
+    return;
+
   if (self->priv->rendered_pixbuf)
     return;
 
@@ -384,6 +411,9 @@ ensure_pixbuf_at_size (GtkIconHelper   *self,
   gint width, height;
   GdkPixbuf *stated;
 
+  if (!check_invalidate_pixbuf (self, context))
+    return;
+
   if (self->priv->rendered_pixbuf)
     return;
 
@@ -497,14 +527,18 @@ static gboolean
 check_invalidate_surface (GtkIconHelper *self,
 			  GtkStyleContext *context)
 {
+  GtkStateFlags state;
   int scale;
 
+  state = gtk_style_context_get_state (context);
   scale = get_scale_factor (self, context);
 
   if ((self->priv->rendered_surface != NULL) &&
+      (self->priv->last_surface_state == state) &&
       (self->priv->last_surface_scale == scale))
     return FALSE;
 
+  self->priv->last_surface_state = state;
   self->priv->last_surface_scale = scale;
 
   if (self->priv->rendered_surface)