[K2, MPP] Cleanup, remove unused FirDeclaration.actualForExpectMap

The concept of actual for expect map is broken and won't work in IDE
properly, since to fill such map we need to analyze all
dependant modules

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/mpp/FirExpectActualMatcherTransformer.kt

@@ -89,12 +89,5 @@ open class FirExpectActualMatcherTransformer(
             scopeSession
         ) ?: mapOf()
         memberDeclaration.expectForActual = expectForActualData
-        for ((compatibility, expectSymbols) in expectForActualData) {
-            if (compatibility.compatible) {
-                for (expectSymbol in expectSymbols) {
-                    expectSymbol.fir.setActualForExpect(session, actualSymbol)
-                }
-            }
-        }
     }
 }

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

@@ -5,23 +5,19 @@
 
 package org.jetbrains.kotlin.fir.declarations
 
-import org.jetbrains.kotlin.fir.FirSession
 import org.jetbrains.kotlin.fir.symbols.FirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.SymbolInternals
 import org.jetbrains.kotlin.fir.symbols.impl.FirFunctionSymbol
 import org.jetbrains.kotlin.fir.symbols.lazyResolveToPhase
 import org.jetbrains.kotlin.resolve.multiplatform.ExpectActualCompatibility
 import org.jetbrains.kotlin.resolve.multiplatform.compatible
-import java.util.*
 
 private object ExpectForActualAttributeKey : FirDeclarationDataKey()
-private object ActualForExpectAttributeKey : FirDeclarationDataKey()
 
 typealias ExpectForActualData = Map<ExpectActualCompatibility<FirBasedSymbol<*>>, List<FirBasedSymbol<*>>>
 
 @SymbolInternals
 var FirDeclaration.expectForActual: ExpectForActualData? by FirDeclarationDataRegistry.data(ExpectForActualAttributeKey)
-private var FirDeclaration.actualForExpectMap: WeakHashMap<FirSession, FirBasedSymbol<*>>? by FirDeclarationDataRegistry.data(ActualForExpectAttributeKey)
 
 fun FirFunctionSymbol<*>.getSingleCompatibleExpectForActualOrNull() =
     (this as FirBasedSymbol<*>).getSingleCompatibleExpectForActualOrNull() as? FirFunctionSymbol<*>
@@ -47,32 +43,3 @@ val FirBasedSymbol<*>.expectForActual: ExpectForActualData?
         return fir.expectForActual
     }
 
-private fun FirDeclaration.getOrCreateActualForExpectMap(): WeakHashMap<FirSession, FirBasedSymbol<*>> {
-    var map = actualForExpectMap
-    if (map != null) return map
-    synchronized(this) {
-        map = actualForExpectMap
-        if (map == null) {
-            map = WeakHashMap()
-            actualForExpectMap = map
-        }
-    }
-    return map!!
-}
-
-@SymbolInternals
-fun FirDeclaration.getActualForExpect(useSiteSession: FirSession): FirBasedSymbol<*>? {
-    return actualForExpectMap?.get(useSiteSession)
-}
-
-fun FirBasedSymbol<*>.getActualForExpect(session: FirSession): FirBasedSymbol<*>? {
-    lazyResolveToPhase(FirResolvePhase.EXPECT_ACTUAL_MATCHING)
-    return fir.getActualForExpect(session)
-}
-
-@SymbolInternals
-fun FirDeclaration.setActualForExpect(useSiteSession: FirSession, actualSymbol: FirBasedSymbol<*>) {
-    val map = getOrCreateActualForExpectMap()
-    map[useSiteSession] = actualSymbol
-}
-