Use original descriptor when trying to obtain source

Also refine `getOriginal` of `DeclarationDescriptorWithSource` for comfortable use

core/descriptors/src/org/jetbrains/kotlin/descriptors/DeclarationDescriptorWithSource.java

@@ -21,4 +21,8 @@ import org.jetbrains.annotations.NotNull;
 public interface DeclarationDescriptorWithSource extends DeclarationDescriptor {
     @NotNull
     SourceElement getSource();
+
+    @Override
+    @NotNull
+    DeclarationDescriptorWithSource getOriginal();
 }

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/AbstractClassDescriptor.java

@@ -66,7 +66,7 @@ public abstract class AbstractClassDescriptor implements ClassDescriptor {
 
     @NotNull
     @Override
-    public DeclarationDescriptor getOriginal() {
+    public DeclarationDescriptorWithSource getOriginal() {
         return this;
     }
 

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/DeclarationDescriptorNonRootImpl.java

@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.descriptors.impl;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor;
 import org.jetbrains.kotlin.descriptors.DeclarationDescriptorNonRoot;
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptorWithSource;
 import org.jetbrains.kotlin.descriptors.SourceElement;
 import org.jetbrains.kotlin.descriptors.annotations.Annotations;
 import org.jetbrains.kotlin.name.Name;
@@ -45,6 +46,12 @@ public abstract class DeclarationDescriptorNonRootImpl
         this.source = source;
     }
 
+    @NotNull
+    @Override
+    public DeclarationDescriptorWithSource getOriginal() {
+        return (DeclarationDescriptorWithSource) super.getOriginal();
+    }
+
     @Override
     @NotNull
     public DeclarationDescriptor getContainingDeclaration() {

core/descriptors/src/org/jetbrains/kotlin/descriptors/impl/LazySubstitutingClassDescriptor.java

@@ -146,7 +146,7 @@ public class LazySubstitutingClassDescriptor implements ClassDescriptor {
 
     @NotNull
     @Override
-    public DeclarationDescriptor getOriginal() {
+    public DeclarationDescriptorWithSource getOriginal() {
         return original.getOriginal();
     }
 

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/JavaResolveExtension.kt

@@ -104,7 +104,7 @@ private fun JavaDescriptorResolver.getContainingScope(member: JavaMember): JetSc
 
 private fun <T : DeclarationDescriptorWithSource> Collection<T>.findByJavaElement(javaElement: JavaElement): T? {
     return firstOrNull { member ->
-        val memberJavaElement = (member.getSource() as? JavaSourceElement)?.javaElement
+        val memberJavaElement = (member.getOriginal().getSource() as? JavaSourceElement)?.javaElement
         when {
             memberJavaElement == javaElement ->
                 true