Fix miscellaneous memory leaks

thumbnailview.cxx: ::ImplInitSettings is called from various
places other than the constructor, so mpItemAttrs must be
freed each time
gloactiongroup.cxx: Must call g_list_free on list returned by
g_hash_table_get_keys

Change-Id: Id5a592520987a1596debdbc48bfa171a537e400b
Reviewed-on: https://gerrit.libreoffice.org/11638Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

sfx2/source/control/thumbnailview.cxx

@@ -59,6 +59,7 @@ enum
 ThumbnailView::ThumbnailView (vcl::Window *pParent, WinBits nWinStyle, bool bDisableTransientChildren)
     : Control( pParent, nWinStyle )
 {
+    mpItemAttrs = NULL;
     ImplInit();
     mbIsTransientChildrenDisabled = bDisableTransientChildren;
 }
@@ -215,7 +216,7 @@ void ThumbnailView::ImplInitSettings( bool bFont, bool bForeground, bool bBackgr
         SetBackground( aColor );
     }
 
-
+    delete mpItemAttrs;
     mpItemAttrs = new ThumbnailItemAttributes;
     mpItemAttrs->aFillColor = maColor.getBColor();
     mpItemAttrs->aHighlightColor = rStyleSettings.GetHighlightColor().getBColor();

vcl/unx/gtk/window/gloactiongroup.cxx

@@ -430,6 +430,8 @@ g_lo_action_group_clear (GLOActionGroup  *group)
     {
         g_lo_action_group_remove (group, (gchar*) element->data);
     }
+
+    g_list_free (keys);
 }
 
 #endif