qmljs: correctly handle js string templates

In most cases we do want to visit the expressions in a function
template. Changing its accept0 would force those not wanting to visit
it to iterate on the templates (currently a linked list), so we add a
visit method explicitly visiting the expression in all the needed
places.

Fixes: QTCREATORBUG-21869
Change-Id: I47733544bfd32eec357810b97242608b8f7de572
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Henning Gründl <henning.gruendl@qt.io>

src/libs/qmljs/jsoncheck.cpp

@@ -84,6 +84,12 @@ void JsonCheck::postVisit(Node *)
     analysis()->m_ranking += previous.m_ranking;
 }
 
+bool JsonCheck::visit(AST::TemplateLiteral *ast)
+{
+    Node::accept(ast->expression, this);
+    return true;
+}
+
 bool JsonCheck::visit(ObjectPattern *ast)
 {
     if (!proceedCheck(JsonValue::Object, ast->lbraceToken))