[JS BE] Do not produce source mapping for fake KtElement

Fix [KT-26701], [KT-12935]

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/util/callUtil.kt

@@ -16,6 +16,7 @@
 
 package org.jetbrains.kotlin.resolve.calls.callUtil
 
+import com.intellij.psi.PsiElement
 import com.intellij.psi.util.PsiTreeUtil
 import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.incremental.KotlinLookupLocation
@@ -246,6 +247,9 @@ val KtElement.isFakeElement: Boolean
         return file is KtFile && file.doNotAnalyze != null
     }
 
+val PsiElement.isFakePsiElement: Boolean
+    get() = this is KtElement && isFakeElement
+
 fun Call.isSafeCall(): Boolean {
     if (this is CallTransformer.CallForImplicitInvoke) {
         //implicit safe 'invoke'