JS: fix inlining of functions derived from other modules

See KT-16408

js/js.tests/test/org/jetbrains/kotlin/js/test/semantics/BoxJsTestGenerated.java

@@ -4754,6 +4754,12 @@ public class BoxJsTestGenerated extends AbstractBoxJsTest {
             doTest(fileName);
         }
 
+        @TestMetadata("fakeFunctionInAnotherModule.kt")
+        public void testFakeFunctionInAnotherModule() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inlineMultiModule/fakeFunctionInAnotherModule.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("importObjectInstance.kt")
         public void testImportObjectInstance() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/box/inlineMultiModule/importObjectInstance.kt");

js/js.translator/src/org/jetbrains/kotlin/js/translate/context/StaticContext.java

@@ -40,10 +40,7 @@ import org.jetbrains.kotlin.js.translate.context.generator.Generator;
 import org.jetbrains.kotlin.js.translate.context.generator.Rule;
 import org.jetbrains.kotlin.js.translate.declaration.ClassModelGenerator;
 import org.jetbrains.kotlin.js.translate.intrinsic.Intrinsics;
-import org.jetbrains.kotlin.js.translate.utils.AnnotationsUtils;
-import org.jetbrains.kotlin.js.translate.utils.JsAstUtils;
-import org.jetbrains.kotlin.js.translate.utils.SignatureUtilsKt;
-import org.jetbrains.kotlin.js.translate.utils.TranslationUtils;
+import org.jetbrains.kotlin.js.translate.utils.*;
 import org.jetbrains.kotlin.name.ClassId;
 import org.jetbrains.kotlin.name.FqName;
 import org.jetbrains.kotlin.resolve.BindingContext;
@@ -805,6 +802,7 @@ public final class StaticContext {
     }
 
     public void addInlineCall(@NotNull CallableDescriptor descriptor) {
+        descriptor = (CallableDescriptor) JsDescriptorUtils.findRealInlineDeclaration(descriptor);
         String tag = Namer.getFunctionTag(descriptor, config);
         JsExpression moduleExpression = exportModuleForInline(DescriptorUtils.getContainingModule(descriptor));
         if (moduleExpression == null) {

js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/JsDescriptorUtils.java

@@ -169,7 +169,7 @@ public final class JsDescriptorUtils {
     }
 
     @Nullable
-    private static FunctionDescriptor findRealDeclaration(FunctionDescriptor descriptor) {
+    private static FunctionDescriptor findRealDeclaration(@NotNull FunctionDescriptor descriptor) {
         if (descriptor.getModality() == Modality.ABSTRACT) return null;
         if (descriptor.getKind().isReal()) return descriptor;
 

js/js.translator/testData/box/inlineMultiModule/fakeFunctionInAnotherModule.kt

@@ -0,0 +1,15 @@
+// EXPECTED_REACHABLE_NODES: 996
+// MODULE: lib
+// FILE: lib1.kt
+open class Parent {
+    inline fun b() = c()
+}
+
+// FILE: lib2.kt
+fun c() = "OK"
+
+// MODULE: main(lib)
+// FILE: main.kt
+class Child : Parent()
+
+fun box() = Child().b()