[FIR] Allow more than one function with some name in local scope

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/scopes/impl/FirLocalScope.kt

@@ -14,13 +14,15 @@ import org.jetbrains.kotlin.name.Name
 class FirLocalScope : FirScope() {
 
     val properties = mutableMapOf<Name, FirVariableSymbol<*>>()
-    val functions = mutableMapOf<Name, FirFunctionSymbol<*>>()
+    val functions = mutableMapOf<Name, MutableList<FirFunctionSymbol<*>>>()
     val classes = mutableMapOf<Name, FirRegularClassSymbol>()
 
     fun storeDeclaration(declaration: FirNamedDeclaration) {
         when (declaration) {
             is FirVariable<*> -> properties[declaration.name] = declaration.symbol
-            is FirSimpleFunction -> functions[declaration.name] = declaration.symbol as FirNamedFunctionSymbol
+            is FirSimpleFunction -> functions.getOrPut(declaration.name) {
+                mutableListOf()
+            }.add(declaration.symbol as FirNamedFunctionSymbol)
             is FirRegularClass -> classes[declaration.name] = declaration.symbol
         }
     }
@@ -30,11 +32,9 @@ class FirLocalScope : FirScope() {
     }
 
     override fun processFunctionsByName(name: Name, processor: (FirFunctionSymbol<*>) -> Unit) {
-        val function = functions[name]
+        for (function in functions[name].orEmpty()) {
-        if (function != null) {
             processor(function)
         }
-
     }
 
     override fun processPropertiesByName(name: Name, processor: (FirCallableSymbol<*>) -> Unit) {

compiler/fir/resolve/testData/resolve/problems/localFunctionsHiding.kt

@@ -5,11 +5,11 @@ interface A {
 fun test_1() {
     fun Int.transform(): Int = 1
     fun A.transform(): Int {
-        return x.<!INAPPLICABLE_CANDIDATE!>transform<!>()
+        return x.transform()
     }
 
     val y = 1
-    y.<!INAPPLICABLE_CANDIDATE!>transform<!>()
+    y.transform()
 }
 
 fun test_2() {

compiler/fir/resolve/testData/resolve/problems/localFunctionsHiding.txt

@@ -10,11 +10,11 @@ FILE: localFunctionsHiding.kt
         }
 
         local final fun R|A|.transform(): R|kotlin/Int| {
-            ^transform this@R|<local>/transform|.R|/A.x|.<Inapplicable(WRONG_RECEIVER): [<local>/transform]>#()
+            ^transform this@R|<local>/transform|.R|/A.x|.R|<local>/transform|()
         }
 
         lval y: R|kotlin/Int| = Int(1)
-        R|<local>/y|.<Inapplicable(WRONG_RECEIVER): [<local>/transform]>#()
+        R|<local>/y|.R|<local>/transform|()
     }
     public final fun test_2(): R|kotlin/Unit| {
         local final fun R|kotlin/Int|.transform(): R|kotlin/Int| {