[JS IR] IC: avoid conflicts in local declaration signatures

compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/ic/IcFileDeserializer.kt

@@ -125,7 +125,7 @@ class IcFileDeserializer(
         { _, s -> s },
         enqueueAllDeclarations = true,
         deserializedSymbols = deserializedSymbols,
-        ::deserializePublicSymbol
+        deserializePublicSymbol = ::deserializePublicSymbol
     )
 
     private val declarationDeserializer = IrDeclarationDeserializer(

compiler/ir/serialization.js/src/org/jetbrains/kotlin/ir/backend/js/lower/serialization/ir/JsIrLinker.kt

@@ -16,10 +16,7 @@ import org.jetbrains.kotlin.ir.builders.TranslationPluginContext
 import org.jetbrains.kotlin.ir.declarations.IrModuleFragment
 import org.jetbrains.kotlin.ir.declarations.persistent.PersistentIrFactory
 import org.jetbrains.kotlin.ir.types.IrTypeSystemContextImpl
-import org.jetbrains.kotlin.ir.util.IrMessageLogger
-import org.jetbrains.kotlin.ir.util.ReferenceSymbolTable
-import org.jetbrains.kotlin.ir.util.SymbolTable
-import org.jetbrains.kotlin.ir.util.TypeTranslator
+import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.library.IrLibrary
 import org.jetbrains.kotlin.library.KotlinAbiVersion
 import org.jetbrains.kotlin.library.KotlinLibrary
@@ -32,7 +29,19 @@ class JsIrLinker(
     private val loweredIcData: Map<ModuleDescriptor, SerializedIcData> = emptyMap(),
     friendModules: Map<String, Collection<String>> = emptyMap(),
     allowUnboundSymbols: Boolean = false
-) : KotlinIrLinker(currentModule, messageLogger, builtIns, symbolTable, emptyList(), allowUnboundSymbols) {
+) : KotlinIrLinker(
+    currentModule,
+    messageLogger,
+    builtIns,
+    symbolTable,
+    emptyList(),
+    allowUnboundSymbols,
+    symbolProcessor = { symbol, idSig ->
+        if (idSig.isLocal) {
+            symbol.privateSignature = IdSignature.CompositeSignature(IdSignature.FileSignature(fileSymbol), idSig)
+        }
+        symbol
+    }) {
 
     override val fakeOverrideBuilder = FakeOverrideBuilder(this, symbolTable, JsManglerIr, IrTypeSystemContextImpl(builtIns), friendModules)