[FIR] Update dummy checker in allopen plugin

plugins/fir/fir-plugin-prototype/src/org/jetbrains/kotlin/fir/plugin/checkers/AllOpenErrors.kt

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.plugin.checkers
+
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.fir.analysis.diagnostics.SourceElementPositioningStrategies
+import org.jetbrains.kotlin.fir.analysis.diagnostics.warning1
+
+object AllOpenErrors {
+    val FUNCTION_WITH_DUMMY_NAME by warning1<PsiElement, String>(SourceElementPositioningStrategies.DECLARATION_NAME)
+}

plugins/fir/fir-plugin-prototype/src/org/jetbrains/kotlin/fir/plugin/checkers/DummyNameChecker.kt

@@ -14,8 +14,9 @@ import org.jetbrains.kotlin.fir.declarations.FirSimpleFunction
 
 object DummyNameChecker : FirSimpleFunctionChecker() {
     override fun check(declaration: FirSimpleFunction, context: CheckerContext, reporter: DiagnosticReporter) {
-        if (declaration.name.asString() == "dummy") {
-            reporter.reportOn(declaration.source, FirErrors.SYNTAX, context)
+        val name = declaration.name.asString()
+        if (name == "dummy") {
+            reporter.reportOn(declaration.source, AllOpenErrors.FUNCTION_WITH_DUMMY_NAME, name, context)
         }
     }
 }

plugins/fir/fir-plugin-prototype/testData/checkers/simple.kt

@@ -1,13 +1,13 @@
-<!SYNTAX_ERROR!>fun dummy(x: Int) {
+fun <!FUNCTION_WITH_DUMMY_NAME!>dummy<!>(x: Int) {
 
-}<!>
+}
 
 class A {
-    <!SYNTAX_ERROR!>fun dummy() {
+    fun <!FUNCTION_WITH_DUMMY_NAME!>dummy<!>() {
 
-    }<!>
+    }
 }
 
 class B {
     val dummy: Int = 1
-}
+}