…brains.kotlin.com.intellij.treeCopyHandler" in kotlin 1.9

Some tests are failing as a result of this.

DO NOT MERGE TO MASTER

…placeWithText(String)`

Up until Kotlin 1.8 the KotlinPsiFactory registered the treeCopyHandler extension point which is needed in order to use the `LeafElement.replaceWithText(String)`. With the Kotlin 1.9 it is no longer possible to register this extension point which results in exception.

The exception does not occur when using method `LeafElement.rawReplaceWithText(String)`.

…` with `AstNode.addChild(AstNode, AstNode)`

Up until Kotlin 1.8 the KotlinPsiFactory registered the treeCopyHandler extension point which is needed in order to use the `PsiElement.addAfter(PsiLeaf, PsiLeaf)`. With the Kotlin 1.9 it is no longer possible to register this extension point which results in exception.

The exception does not occur when using method `AstNode.addChild(AstNode, AstNode)`. Note that this method inserts the new node (first) argument *before* the second argument node and as of that is not a simple replacement of the `PsiElement.addAfter(PsiElement, PsiElement)`.

…needed

…addChild(AstNode, AstNode)` and `AstNode.removeChild(AstNode)`

Up until Kotlin 1.8 the KotlinPsiFactory registered the treeCopyHandler extension point which is needed in order to use the `PsiElement.replace(PsiElement)`. With the Kotlin 1.9 it is no longer possible to register this extension point which results in exception.

…addChild(AstNode, AstNode)` and `AstNode.removeChild(AstNode)` [bugfix]

Up until Kotlin 1.8 the KotlinPsiFactory registered the treeCopyHandler extension point which is needed in order to use the `PsiElement.replace(PsiElement)`. With the Kotlin 1.9 it is no longer possible to register this extension point which results in exception.