[FIR] Use stubs for raw name of parameter

Eighth step for ^KT-52615
Add comment for getRawName()
diff --git a/compiler/psi/src/org/jetbrains/kotlin/psi/stubs/StubInterfaces.kt b/compiler/psi/src/org/jetbrains/kotlin/psi/stubs/StubInterfaces.kt
index fabf832..1867523 100644
--- a/compiler/psi/src/org/jetbrains/kotlin/psi/stubs/StubInterfaces.kt
+++ b/compiler/psi/src/org/jetbrains/kotlin/psi/stubs/StubInterfaces.kt
@@ -119,6 +119,11 @@
     fun isMutable(): Boolean
     fun hasValOrVar(): Boolean
     fun hasDefaultValue(): Boolean
+
+    /**
+     * Returns raw name, i. e. text of name identifier. Returns same value as getName() unless name is quoted. Return null if and only if
+     * name will return null
+     */
     fun getRawName(): String?
 }