Provide implicit receiver to extension property initializer

This is safe because initializers for extension properties are forbidden
anyway, we'll just won't be generating noisy error messages about non-existent
'this'

compiler/frontend/src/org/jetbrains/jet/lang/resolve/DescriptorResolver.java

@@ -21,7 +21,6 @@ import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.intellij.lang.ASTNode;
 import com.intellij.psi.PsiElement;
-import com.intellij.psi.util.PsiTreeUtil;
 import kotlin.Function0;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -937,11 +936,13 @@ public class DescriptorResolver {
             }
         }
 
-        ReceiverParameterDescriptor receiverDescriptor = DescriptorFactory.createReceiverParameterForCallable(propertyDescriptor,
-                                                                                                              receiverType);
+        ReceiverParameterDescriptor receiverDescriptor =
+                DescriptorFactory.createReceiverParameterForCallable(propertyDescriptor, receiverType);
+
+        ReceiverParameterDescriptor implicitInitializerReceiver = property.hasDelegate() ? NO_RECEIVER_PARAMETER : receiverDescriptor;
 
         JetScope propertyScope = JetScopeUtils.getPropertyDeclarationInnerScope(propertyDescriptor, scope, typeParameterDescriptors,
-                                                                                NO_RECEIVER_PARAMETER, trace);
+                                                                                implicitInitializerReceiver, trace);
 
         JetType type = getVariableType(propertyDescriptor, propertyScope, property, dataFlowInfo, true, trace);
 

compiler/testData/diagnostics/tests/scopes/initializerScopeOfExtensionProperty.kt

@@ -1,10 +1,10 @@
 package i
 
-val <T> List<T>.length = <!EXTENSION_PROPERTY_WITH_BACKING_FIELD!><!UNRESOLVED_REFERENCE!>size<!>()<!>
+val <T> List<T>.length = <!EXTENSION_PROPERTY_WITH_BACKING_FIELD!>size()<!>
 
 val <T> List<T>.length1 : Int get() = size()
 
-val String.bd = <!EXTENSION_PROPERTY_WITH_BACKING_FIELD!><!NO_THIS!>this<!> <!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>+<!> "!"<!>
+val String.bd = <!EXTENSION_PROPERTY_WITH_BACKING_FIELD!>this + "!"<!>
 
 val String.bd1 : String get() = this + "!"
 
@@ -13,7 +13,7 @@ class A {
     val ii : Int = 1
 }
 
-val A.foo = <!UNRESOLVED_REFERENCE, EXTENSION_PROPERTY_WITH_BACKING_FIELD!>ii<!>
+val A.foo = <!EXTENSION_PROPERTY_WITH_BACKING_FIELD!>ii<!>
 
 val A.foo1 : Int get() = ii