diff --git a/compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaBeansExtensionsScope.kt b/compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaBeansExtensionsScope.kt
index fe7941e5081..5834b3c763e 100644
--- a/compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaBeansExtensionsScope.kt
+++ b/compiler/frontend.java/src/org/jetbrains/kotlin/synthetic/JavaBeansExtensionsScope.kt
@@ -127,7 +127,7 @@ class JavaBeansExtensionsScope(storageManager: StorageManager) : JetScope by Jet
                && descriptor.getVisibility() == Visibilities.PUBLIC
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> {
         return collectSyntheticPropertiesByName(null, receiverType.makeNotNullable(), name) ?: emptyList()
     }
 
@@ -146,7 +146,7 @@ class JavaBeansExtensionsScope(storageManager: StorageManager) : JetScope by Jet
         return result
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> {
         val result = ArrayList<PropertyDescriptor>()
         result.collectSyntheticProperties(receiverType.makeNotNullable())
         return result
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/AllUnderImportsScope.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/AllUnderImportsScope.kt
index 94a9868fae2..f4218d6fc5c 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/AllUnderImportsScope.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/AllUnderImportsScope.kt
@@ -53,11 +53,11 @@ class AllUnderImportsScope : JetScope {
         return scopes.flatMap { it.getFunctions(name) }
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> {
         return scopes.flatMap { it.getSyntheticExtensionProperties(receiverType, name) }
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> {
         return scopes.flatMap { it.getSyntheticExtensionProperties(receiverType) }
     }
 
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/LazyImportScope.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/LazyImportScope.kt
index 903d61c4e9e..e6a157b09c8 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/LazyImportScope.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/LazyImportScope.kt
@@ -255,17 +255,17 @@ class LazyImportScope(
         return importResolver.collectFromImports(name, LookupMode.EVERYTHING) { scope, name -> scope.getFunctions(name) }
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> {
         if (filteringKind == FilteringKind.INVISIBLE_CLASSES) return listOf()
         return importResolver.collectFromImports(name, LookupMode.EVERYTHING) { scope, name -> scope.getSyntheticExtensionProperties(receiverType, name) }
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> {
         // we do not perform any filtering by visibility here because all descriptors from both visible/invisible filter scopes are to be added anyway
         if (filteringKind == FilteringKind.INVISIBLE_CLASSES) return listOf()
 
         return importResolver.resolveSession.getStorageManager().compute {
-            importResolver.indexedImports.imports.flatMapTo(LinkedHashSet<VariableDescriptor>()) { import ->
+            importResolver.indexedImports.imports.flatMapTo(LinkedHashSet<PropertyDescriptor>()) { import ->
                 importResolver.getImportScope(import, LookupMode.EVERYTHING).getSyntheticExtensionProperties(receiverType)
             }
         }
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/AbstractScopeAdapter.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/AbstractScopeAdapter.kt
index aee4d5f6423..bd2484fe4fe 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/AbstractScopeAdapter.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/AbstractScopeAdapter.kt
@@ -47,11 +47,11 @@ public abstract class AbstractScopeAdapter : JetScope {
         return workerScope.getProperties(name)
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> {
         return workerScope.getSyntheticExtensionProperties(receiverType, name)
     }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor> {
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> {
         return workerScope.getSyntheticExtensionProperties(receiverType)
     }
 
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/ChainedScope.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/ChainedScope.kt
index 7d1319fbeb4..7ba44c9658b 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/ChainedScope.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/ChainedScope.kt
@@ -65,10 +65,10 @@ public open class ChainedScope(
     override fun getFunctions(name: Name): Collection<FunctionDescriptor>
             = getFromAllScopes { it.getFunctions(name) }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor>
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor>
             = getFromAllScopes { it.getSyntheticExtensionProperties(receiverType, name) }
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor>
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor>
             = getFromAllScopes { it.getSyntheticExtensionProperties(receiverType) }
 
     override fun getImplicitReceiversHierarchy(): List<ReceiverParameterDescriptor> {
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/FilteringScope.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/FilteringScope.kt
index 650c8ff0f8c..5dc3782cee5 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/FilteringScope.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/FilteringScope.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.resolve.scopes
 
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.JetType
 import org.jetbrains.kotlin.utils.Printer
@@ -36,9 +37,9 @@ public class FilteringScope(private val workerScope: JetScope, private val predi
 
     override fun getProperties(name: Name) = workerScope.getProperties(name).filter(predicate)
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name) = workerScope.getSyntheticExtensionProperties(receiverType, name).filter(predicate)
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> = workerScope.getSyntheticExtensionProperties(receiverType, name).filter(predicate)
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType) = workerScope.getSyntheticExtensionProperties(receiverType).filter(predicate)
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> = workerScope.getSyntheticExtensionProperties(receiverType).filter(predicate)
 
     override fun getLocalVariable(name: Name) = filterDescriptor(workerScope.getLocalVariable(name))
 
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScope.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScope.kt
index d2ddc74eca1..102d79a2f7a 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScope.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScope.kt
@@ -35,9 +35,9 @@ public trait JetScope {
 
     public fun getFunctions(name: Name): Collection<FunctionDescriptor>
 
-    public fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor>
+    public fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor>
 
-    public fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor>
+    public fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor>
 
     public fun getContainingDeclaration(): DeclarationDescriptor
 
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScopeImpl.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScopeImpl.kt
index 011ed035050..e55a691dffc 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScopeImpl.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/JetScopeImpl.kt
@@ -32,9 +32,9 @@ public abstract class JetScopeImpl : JetScope {
 
     override fun getFunctions(name: Name): Collection<FunctionDescriptor> = setOf()
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<VariableDescriptor> = listOf()
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> = listOf()
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<VariableDescriptor> = listOf()
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> = listOf()
 
     override fun getDeclarationsByLabel(labelName: Name): Collection<DeclarationDescriptor> = listOf()
 
diff --git a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/SubstitutingScope.kt b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/SubstitutingScope.kt
index 2d53c9f2ad9..d1533271a52 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/SubstitutingScope.kt
+++ b/core/descriptors/src/org/jetbrains/kotlin/resolve/scopes/SubstitutingScope.kt
@@ -17,6 +17,7 @@
 package org.jetbrains.kotlin.resolve.scopes
 
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.descriptors.ReceiverParameterDescriptor
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.types.JetType
@@ -69,9 +70,9 @@ public class SubstitutingScope(private val workerScope: JetScope, private val su
 
     override fun getFunctions(name: Name) = substitute(workerScope.getFunctions(name))
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name) = substitute(workerScope.getSyntheticExtensionProperties(receiverType, name))
+    override fun getSyntheticExtensionProperties(receiverType: JetType, name: Name): Collection<PropertyDescriptor> = substitute(workerScope.getSyntheticExtensionProperties(receiverType, name))
 
-    override fun getSyntheticExtensionProperties(receiverType: JetType) = substitute(workerScope.getSyntheticExtensionProperties(receiverType))
+    override fun getSyntheticExtensionProperties(receiverType: JetType): Collection<PropertyDescriptor> = substitute(workerScope.getSyntheticExtensionProperties(receiverType))
 
     override fun getPackage(name: Name) = workerScope.getPackage(name)
 
diff --git a/core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java b/core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java
index 6c0716e61dc..4c1299be7ec 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/types/ErrorUtils.java
@@ -88,12 +88,12 @@ public class ErrorUtils {
         @NotNull
         @Override
         public Set<VariableDescriptor> getProperties(@NotNull Name name) {
-            return ERROR_PROPERTY_GROUP;
+            return ERROR_VARIABLE_GROUP;
         }
 
         @NotNull
         @Override
-        public Collection<VariableDescriptor> getSyntheticExtensionProperties(
+        public Collection<PropertyDescriptor> getSyntheticExtensionProperties(
                 @NotNull JetType receiverType, @NotNull Name name
         ) {
             return ERROR_PROPERTY_GROUP;
@@ -101,7 +101,7 @@ public class ErrorUtils {
 
         @NotNull
         @Override
-        public Collection<VariableDescriptor> getSyntheticExtensionProperties(@NotNull JetType receiverType) {
+        public Collection<PropertyDescriptor> getSyntheticExtensionProperties(@NotNull JetType receiverType) {
             return ERROR_PROPERTY_GROUP;
         }
 
@@ -209,7 +209,7 @@ public class ErrorUtils {
 
         @NotNull
         @Override
-        public Collection<VariableDescriptor> getSyntheticExtensionProperties(
+        public Collection<PropertyDescriptor> getSyntheticExtensionProperties(
                 @NotNull JetType receiverType, @NotNull Name name
         ) {
             throw new IllegalStateException();
@@ -217,7 +217,7 @@ public class ErrorUtils {
 
         @NotNull
         @Override
-        public Collection<VariableDescriptor> getSyntheticExtensionProperties(@NotNull JetType receiverType) {
+        public Collection<PropertyDescriptor> getSyntheticExtensionProperties(@NotNull JetType receiverType) {
             throw new IllegalStateException();
         }
 
@@ -333,9 +333,10 @@ public class ErrorUtils {
     }
 
     private static final JetType ERROR_PROPERTY_TYPE = createErrorType("<ERROR PROPERTY TYPE>");
-    private static final VariableDescriptor ERROR_PROPERTY = createErrorProperty();
+    private static final PropertyDescriptor ERROR_PROPERTY = createErrorProperty();
 
-    private static final Set<VariableDescriptor> ERROR_PROPERTY_GROUP = Collections.singleton(ERROR_PROPERTY);
+    private static final Set<VariableDescriptor> ERROR_VARIABLE_GROUP = Collections.<VariableDescriptor>singleton(ERROR_PROPERTY);
+    private static final Set<PropertyDescriptor> ERROR_PROPERTY_GROUP = Collections.singleton(ERROR_PROPERTY);
 
     @NotNull
     private static PropertyDescriptorImpl createErrorProperty() {