Completion: escaping of named arguments

idea/testData/completion/handlers/NamedParameterKeywordName.kt

@@ -0,0 +1,5 @@
+fun foo(`class`: Int) {}
+
+fun test() {
+    foo(<caret>)
+}

idea/testData/completion/handlers/NamedParameterKeywordName.kt.after

@@ -0,0 +1,5 @@
+fun foo(`class`: Int) {}
+
+fun test() {
+    foo(`class` = <caret>)
+}