Rename FileDialog's folder icon custom color to `folder_icon_modulate`

The custom color introduced in be8d569744e4eed9acb313d355d96e6989e92087
had the same name as the "folder" icon, which could cause conflicts
in the generated documentation.

The new name is also more self-explanatory.

doc/classes/FileDialog.xml

@@ -134,6 +134,8 @@
 		</theme_item>
 		<theme_item name="folder" type="Texture">
 		</theme_item>
+		<theme_item name="folder_icon_modulate" type="Color" default="Color( 1, 1, 1, 1 )">
+		</theme_item>
 		<theme_item name="parent_folder" type="Texture">
 		</theme_item>
 		<theme_item name="reload" type="Texture">

editor/editor_file_dialog.cpp

@@ -257,7 +257,7 @@ void EditorFileDialog::_post_popup() {
 
 	if (is_visible_in_tree()) {
 		Ref<Texture> folder = get_icon("folder", "FileDialog");
-		const Color folder_color = get_color("folder", "FileDialog");
+		const Color folder_color = get_color("folder_icon_modulate", "FileDialog");
 		recent->clear();
 
 		bool res = access == ACCESS_RESOURCES;
@@ -736,7 +736,7 @@ void EditorFileDialog::update_file_list() {
 	dir_access->list_dir_begin();
 
 	Ref<Texture> folder = get_icon("folder", "FileDialog");
-	const Color folder_color = get_color("folder", "FileDialog");
+	const Color folder_color = get_color("folder_icon_modulate", "FileDialog");
 	List<String> files;
 	List<String> dirs;
 
@@ -1204,7 +1204,7 @@ void EditorFileDialog::_update_favorites() {
 
 	String current = get_current_dir();
 	Ref<Texture> folder_icon = get_icon("Folder", "EditorIcons");
-	const Color folder_color = get_color("folder", "FileDialog");
+	const Color folder_color = get_color("folder_icon_modulate", "FileDialog");
 	favorites->clear();
 
 	favorite->set_pressed(false);

editor/editor_themes.cpp

@@ -1068,7 +1068,7 @@ Ref<Theme> create_editor_theme(const Ref<Theme> p_theme) {
 	theme->set_icon("folder", "FileDialog", theme->get_icon("Folder", "EditorIcons"));
 	// Use a different color for folder icons to make them easier to distinguish from files.
 	// On a light theme, the icon will be dark, so we need to lighten it before blending it with the accent color.
-	theme->set_color("folder", "FileDialog", (dark_theme ? Color(1, 1, 1) : Color(5, 5, 5)).linear_interpolate(accent_color, 0.7));
+	theme->set_color("folder_icon_modulate", "FileDialog", (dark_theme ? Color(1, 1, 1) : Color(5, 5, 5)).linear_interpolate(accent_color, 0.7));
 	theme->set_color("files_disabled", "FileDialog", font_color_disabled);
 
 	// color picker

editor/filesystem_dock.cpp

@@ -64,7 +64,7 @@ bool FileSystemDock::_create_tree(TreeItem *p_parent, EditorFileSystemDirectory
 
 	subdirectory_item->set_text(0, dname);
 	subdirectory_item->set_icon(0, get_icon("Folder", "EditorIcons"));
-	subdirectory_item->set_icon_color(0, get_color("folder", "FileDialog"));
+	subdirectory_item->set_icon_color(0, get_color("folder_icon_modulate", "FileDialog"));
 	subdirectory_item->set_selectable(0, true);
 	String lpath = p_dir->get_path();
 	subdirectory_item->set_metadata(0, lpath);
@@ -187,7 +187,7 @@ void FileSystemDock::_update_tree(const Vector<String> &p_uncollapsed_paths, boo
 			continue;
 
 		Ref<Texture> folder_icon = get_icon("Folder", "EditorIcons");
-		const Color folder_color = get_color("folder", "FileDialog");
+		const Color folder_color = get_color("folder_icon_modulate", "FileDialog");
 
 		String text;
 		Ref<Texture> icon;
@@ -646,7 +646,7 @@ void FileSystemDock::_update_file_list(bool p_keep_selection) {
 	}
 
 	Ref<Texture> folder_icon = (use_thumbnails) ? folder_thumbnail : get_icon("folder", "FileDialog");
-	const Color folder_color = get_color("folder", "FileDialog");
+	const Color folder_color = get_color("folder_icon_modulate", "FileDialog");
 
 	// Build the FileInfo list
 	List<FileInfo> filelist;

scene/gui/file_dialog.cpp

@@ -400,7 +400,7 @@ void FileDialog::update_file_list() {
 
 	TreeItem *root = tree->create_item();
 	Ref<Texture> folder = get_icon("folder");
-	const Color folder_color = get_color("folder");
+	const Color folder_color = get_color("folder_icon_modulate");
 	List<String> files;
 	List<String> dirs;
 

scene/resources/default_theme/default_theme.cpp

@@ -760,7 +760,7 @@ void fill_default_theme(Ref<Theme> &theme, const Ref<Font> &default_font, const
 	// FileDialog
 
 	theme->set_icon("folder", "FileDialog", make_icon(icon_folder_png));
-	theme->set_color("folder", "FileDialog", Color(1, 1, 1));
+	theme->set_color("folder_icon_modulate", "FileDialog", Color(1, 1, 1));
 	theme->set_color("files_disabled", "FileDialog", Color(0, 0, 0, 0.7));
 
 	// colorPicker