KT-12793 Code completion doesn't suggest abstract protected extension methods

#KT-12793 Fixed

idea/idea-completion/testData/basic/common/ProtectedExtensionMethod.kt

@@ -0,0 +1,9 @@
+abstract class ProtectedTest {
+    fun foo() {
+        "".<caret>
+    }
+
+    abstract protected fun String.bar()
+}
+
+// EXIST: bar

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JSBasicCompletionTestGenerated.java

@@ -649,6 +649,12 @@ public class JSBasicCompletionTestGenerated extends AbstractJSBasicCompletionTes
             doTest(fileName);
         }
 
+        @TestMetadata("ProtectedExtensionMethod.kt")
+        public void testProtectedExtensionMethod() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/ProtectedExtensionMethod.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("QualifiedSuperMembers.kt")
         public void testQualifiedSuperMembers() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/QualifiedSuperMembers.kt");

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/JvmBasicCompletionTestGenerated.java

@@ -649,6 +649,12 @@ public class JvmBasicCompletionTestGenerated extends AbstractJvmBasicCompletionT
             doTest(fileName);
         }
 
+        @TestMetadata("ProtectedExtensionMethod.kt")
+        public void testProtectedExtensionMethod() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/ProtectedExtensionMethod.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("QualifiedSuperMembers.kt")
         public void testQualifiedSuperMembers() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/idea-completion/testData/basic/common/QualifiedSuperMembers.kt");

idea/idea-core/src/org/jetbrains/kotlin/idea/core/descriptorUtils.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.lexer.KtModifierKeywordToken
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.KtExpression
 import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.descriptorUtil.isExtension
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.OverridingUtil
 import org.jetbrains.kotlin.resolve.findOriginalTopMostOverriddenDescriptors
@@ -62,7 +63,8 @@ private fun DeclarationDescriptorWithVisibility.isVisible(
 
     if (bindingContext == null || resolutionScope == null) return false
 
-    if (receiverExpression != null) {
+    // for extension it makes no sense to check explicit receiver because we need dispatch receiver which is implicit in this case
+    if (receiverExpression != null && !isExtension) {
         val receiverType = bindingContext.getType(receiverExpression) ?: return false
         val explicitReceiver = ExpressionReceiver.create(receiverExpression, receiverType, bindingContext)
         return Visibilities.isVisible(explicitReceiver, this, from)