Make Kotlin light classes pass "element instanceof StubBasedPsiElement" in LocalSearchScope scope

compiler/light-classes/src/org/jetbrains/kotlin/asJava/KotlinLightClassForExplicitDeclaration.kt

@@ -25,7 +25,9 @@ import com.intellij.psi.impl.light.LightClass
 import com.intellij.psi.impl.light.LightMethod
 import com.intellij.psi.scope.PsiScopeProcessor
 import com.intellij.psi.search.SearchScope
+import com.intellij.psi.stubs.IStubElementType
 import com.intellij.psi.stubs.PsiClassHolderFileStub
+import com.intellij.psi.stubs.StubElement
 import com.intellij.psi.util.CachedValue
 import com.intellij.psi.util.CachedValuesManager
 import com.intellij.util.IncorrectOperationException
@@ -40,6 +42,7 @@ import org.jetbrains.kotlin.name.FqNameUnsafe
 import org.jetbrains.kotlin.platform.JavaToKotlinClassMap
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
+import org.jetbrains.kotlin.psi.stubs.KotlinClassOrObjectStub
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.jvm.JvmClassName
 import javax.swing.Icon
@@ -47,8 +50,8 @@ import javax.swing.Icon
 public open class KotlinLightClassForExplicitDeclaration(
         manager: PsiManager,
         private val classFqName: FqName, // FqName of (possibly inner) class
-        protected val classOrObject: JetClassOrObject) : KotlinWrappingLightClass(manager), JetJavaMirrorMarker {
+        protected val classOrObject: JetClassOrObject)
-
+: KotlinWrappingLightClass(manager), JetJavaMirrorMarker, StubBasedPsiElement<KotlinClassOrObjectStub<out JetClassOrObject>> {
     private var delegate: PsiClass? = null
 
     private fun getLocalClassParent(): PsiElement? {
@@ -376,6 +379,9 @@ public open class KotlinLightClassForExplicitDeclaration(
 
     override fun getUseScope(): SearchScope = getOrigin().useScope
 
+    override fun getElementType(): IStubElementType<out StubElement<*>, *>? = classOrObject.elementType
+    override fun getStub(): KotlinClassOrObjectStub<out JetClassOrObject>? = classOrObject.stub
+
     companion object {
         private val JAVA_API_STUB = Key.create<CachedValue<OutermostKotlinClassLightClassData>>("JAVA_API_STUB")
 

idea/testData/navigation/implementations/multifile/ImplementJavaInnerInterface/ImplementJavaInnerInterface.java

@@ -0,0 +1,21 @@
+public class ImplementJavaInnerInterface {
+    interface Test {
+        void foo();
+    }
+
+    void test() {
+        Test test = new Test() {
+            @Override
+            public void foo() {
+
+            }
+        };
+    }
+
+    void usage(Test test) {
+        test.<caret>foo();
+    }
+}
+
+// REF: (in KotlinTest).foo()
+// REF: <anonymous>.foo()

idea/testData/navigation/implementations/multifile/ImplementJavaInnerInterface/ImplementJavaInnerInterface.kt

@@ -0,0 +1,3 @@
+class KotlinTest : ImplementJavaInnerInterface.Test {
+    override fun foo() {}
+}

idea/tests/org/jetbrains/kotlin/idea/navigation/JetGotoImplementationMultifileTest.java

@@ -62,10 +62,18 @@ public class JetGotoImplementationMultifileTest extends JetLightCodeInsightFixtu
         doKotlinJavaTest();
     }
 
+    public void testImplementJavaInnerInterface() throws Exception {
+        doJavaKotlinTest();
+    }
+
     private void doKotlinJavaTest() throws Exception {
         doMultifileTest(getTestName(false) + ".kt", getTestName(false) + ".java");
     }
 
+    private void doJavaKotlinTest() throws Exception {
+        doMultifileTest(getTestName(false) + ".java", getTestName(false) + ".kt");
+    }
+
     @NotNull
     @Override
     protected LightProjectDescriptor getProjectDescriptor() {

idea/tests/org/jetbrains/kotlin/test/ReferenceUtils.java

@@ -18,6 +18,7 @@ package org.jetbrains.kotlin.test;
 
 import com.intellij.navigation.ItemPresentation;
 import com.intellij.navigation.NavigationItem;
+import com.intellij.psi.PsiAnonymousClass;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiPackage;
 import com.intellij.psi.util.PsiTreeUtil;
@@ -49,6 +50,9 @@ public final class ReferenceUtils {
 
         String presentableText = presentation.getPresentableText();
         String locationString = presentation.getLocationString();
+        if (locationString == null && element.getParent() instanceof PsiAnonymousClass) {
+            locationString = "<anonymous>";
+        }
         return locationString == null || navigationElement instanceof PsiPackage
                // for PsiPackage, presentableText is FQ name of current package
                ? presentableText