QmlDesigner: Use a static const QSet for keyword list

Makes the lookup faster.

Also sort the keywords.

Change-Id: I25ce0f2d1de7be572fecccc09b5ec12d81152e95
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/qmldesigner/designercore/model/modelnode.cpp

@@ -29,8 +29,6 @@
 #include <model.h>
 #include <nodemetainfo.h>
 #include "internalnode_p.h"
-#include <QHash>
-#include <QTextStream>
 #include "invalidargumentexception.h"
 #include "invalididexception.h"
 #include "invalidmodelnodeexception.h"
@@ -44,6 +42,10 @@
 #include "nodeproperty.h"
 #include <rewriterview.h>
 
+#include <QHash>
+#include <QSet>
+#include <QTextStream>
+
 namespace QmlDesigner {
 using namespace QmlDesigner::Internal;
 
@@ -143,7 +145,7 @@ QString ModelNode::validId()
 
 static bool idIsQmlKeyWord(const QString& id)
 {
-    QStringList keywords = { "import",
+    static const QSet<QString> keywords = {
         "as",
         "break",
         "case",
@@ -158,6 +160,7 @@ static bool idIsQmlKeyWord(const QString& id)
         "for",
         "function",
         "if",
+        "import",
         "in",
         "instanceof",
         "new",
@@ -170,7 +173,8 @@ static bool idIsQmlKeyWord(const QString& id)
         "var",
         "void",
         "while",
-                             "with" };
+        "with"
+    };
 
     return keywords.contains(id);
 }