Fix expect/actual gutters for declarations in the same module.

Fixed #KT-33510.

idea/idea-analysis/src/org/jetbrains/kotlin/idea/util/expectActualUtil.kt

@@ -28,7 +28,9 @@ import org.jetbrains.kotlin.resolve.descriptorUtil.module
 import org.jetbrains.kotlin.resolve.lazy.BodyResolveMode
 import org.jetbrains.kotlin.resolve.multiplatform.ExpectedActualResolver
 
-internal fun MemberDescriptor.expectedDescriptors() = module.implementedDescriptors.mapNotNull { it.declarationOf(this) }
+internal fun MemberDescriptor.expectedDescriptors() =
+    (module.implementedDescriptors + module)
+        .mapNotNull { it.declarationOf(this) }
 
 // TODO: Sort out the cases with multiple expected descriptors
 fun MemberDescriptor.expectedDescriptor() = expectedDescriptors().firstOrNull()
@@ -101,7 +103,7 @@ fun DeclarationDescriptor.actualsForExpected(): Collection<DeclarationDescriptor
     if (this is MemberDescriptor) {
         if (!this.isExpect) return emptyList()
 
-        return module.implementingDescriptors.flatMap { it.actualsFor(this) }
+        return (module.implementingDescriptors + module).flatMap { it.actualsFor(this) }
     }
 
     if (this is ValueParameterDescriptor) {
@@ -111,6 +113,8 @@ fun DeclarationDescriptor.actualsForExpected(): Collection<DeclarationDescriptor
     return emptyList()
 }
 
+fun KtDeclaration.hasAtLeastOneActual() = actualsForExpected().isNotEmpty()
+
 // null means "any platform" here
 fun KtDeclaration.actualsForExpected(module: Module? = null): Set<KtDeclaration> =
     resolveToDescriptorIfAny(BodyResolveMode.FULL)

idea/src/org/jetbrains/kotlin/idea/highlighter/markers/KotlinLineMarkerProvider.kt

@@ -26,18 +26,13 @@ import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.asJava.LightClassUtil
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.descriptors.CallableMemberDescriptor
-import org.jetbrains.kotlin.descriptors.MemberDescriptor
 import org.jetbrains.kotlin.descriptors.Modality
+import org.jetbrains.kotlin.idea.KotlinBundle
 import org.jetbrains.kotlin.idea.caches.lightClasses.KtFakeLightClass
 import org.jetbrains.kotlin.idea.caches.lightClasses.KtFakeLightMethod
-import org.jetbrains.kotlin.idea.caches.project.implementedDescriptors
-import org.jetbrains.kotlin.idea.caches.project.implementingDescriptors
-import org.jetbrains.kotlin.idea.caches.resolve.findModuleDescriptor
 import org.jetbrains.kotlin.idea.core.isInheritable
 import org.jetbrains.kotlin.idea.core.isOverridable
-import org.jetbrains.kotlin.idea.core.toDescriptor
 import org.jetbrains.kotlin.idea.editor.fixers.startLine
-import org.jetbrains.kotlin.idea.KotlinBundle
 import org.jetbrains.kotlin.idea.presentation.DeclarationByModuleRenderer
 import org.jetbrains.kotlin.idea.search.declarationsSearch.toPossiblyFakeLightMethods
 import org.jetbrains.kotlin.idea.util.*
@@ -464,11 +459,7 @@ private fun collectActualMarkers(
 ) {
     if (!KotlinLineMarkerOptions.actualOption.isEnabled) return
     if (declaration.requiresNoMarkers()) return
-
-    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
-    val commonModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
-
-    if (commonModuleDescriptor.implementingDescriptors.none { it.hasActualsFor(descriptor) }) return
+    if (!declaration.hasAtLeastOneActual()) return
 
     val anchor = declaration.expectOrActualAnchor
 
@@ -496,10 +487,7 @@ private fun collectExpectedMarkers(
     if (!KotlinLineMarkerOptions.expectOption.isEnabled) return
 
     if (declaration.requiresNoMarkers()) return
-
-    val descriptor = declaration.toDescriptor() as? MemberDescriptor ?: return
-    val platformModuleDescriptor = declaration.containingKtFile.findModuleDescriptor()
-    if (!platformModuleDescriptor.implementedDescriptors.any { it.hasDeclarationOf(descriptor) }) return
+    if (!declaration.hasMatchingExpected()) return
 
     val anchor = declaration.expectOrActualAnchor