FIR: make JavaClassEnhancementScope use-site, get rid of scope providers

Related to KT-29937

compiler/fir/tree/src/org/jetbrains/kotlin/fir/declarations/FirClass.kt

@@ -6,8 +6,10 @@
 package org.jetbrains.kotlin.fir.declarations
 
 import org.jetbrains.kotlin.descriptors.ClassKind
+import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.expressions.FirAnnotationContainer
 import org.jetbrains.kotlin.fir.expressions.FirStatement
+import org.jetbrains.kotlin.fir.scopes.FirScope
 import org.jetbrains.kotlin.fir.types.ConeClassLikeType
 import org.jetbrains.kotlin.fir.types.FirTypeRef
 import org.jetbrains.kotlin.fir.types.coneTypeSafe
@@ -19,6 +21,8 @@ interface FirClass : FirDeclarationContainer, FirStatement, FirAnnotationContain
 
     val classKind: ClassKind
 
+    fun buildClassSpecificUseSiteScope(useSiteSession: FirSession): FirScope? = null
+
     override fun <R, D> accept(visitor: FirVisitor<R, D>, data: D): R =
         visitor.visitClass(this, data)
 

compiler/fir/tree/src/org/jetbrains/kotlin/fir/scopes/FirScope.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. 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.scopes
+
+import org.jetbrains.kotlin.fir.scopes.ProcessorAction.NEXT
+import org.jetbrains.kotlin.fir.symbols.ConeClassifierSymbol
+import org.jetbrains.kotlin.fir.symbols.ConeFunctionSymbol
+import org.jetbrains.kotlin.fir.symbols.ConePropertySymbol
+import org.jetbrains.kotlin.name.Name
+
+interface FirScope {
+    fun processClassifiersByName(
+        name: Name,
+        position: FirPosition,
+        processor: (ConeClassifierSymbol) -> Boolean
+    ): Boolean = true
+
+    fun processFunctionsByName(
+        name: Name,
+        processor: (ConeFunctionSymbol) -> ProcessorAction
+    ): ProcessorAction = NEXT
+
+    fun processPropertiesByName(
+        name: Name,
+        processor: (ConePropertySymbol) -> ProcessorAction
+    ): ProcessorAction = NEXT
+}
+
+enum class FirPosition(val allowTypeParameters: Boolean = true) {
+    SUPER_TYPE_OR_EXPANSION(allowTypeParameters = false),
+    OTHER
+}
+
+enum class ProcessorAction {
+    STOP,
+    NEXT;
+
+    operator fun not(): Boolean {
+        return when (this) {
+            STOP -> true
+            NEXT -> false
+        }
+    }
+
+    fun next() = this == NEXT
+}