Avoid exception from DocumentImpl.setInBulkUpdate in reformat inspection

#KT-21036 Fixed

idea/src/org/jetbrains/kotlin/idea/formatter/CollectChangesWithoutApplyModel.kt

@@ -1,17 +1,6 @@
 /*
- * Copyright 2010-2017 JetBrains s.r.o.
+ * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- *
+ * that can be found in the license/LICENSE.txt file.
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
  */
 
 package org.jetbrains.kotlin.idea.formatter
@@ -20,6 +9,7 @@ import com.intellij.formatting.Block
 import com.intellij.formatting.FormattingDocumentModel
 import com.intellij.formatting.FormattingModel
 import com.intellij.lang.ASTNode
+import com.intellij.openapi.editor.impl.DocumentImpl
 import com.intellij.openapi.util.Key
 import com.intellij.openapi.util.TextRange
 import com.intellij.psi.PsiFile
@@ -61,7 +51,7 @@ fun collectFormattingChanges(file: PsiFile): Set<FormattingChange> {
 }
 
 private class CollectChangesWithoutApplyModel(val file: PsiFile, val block: Block) : FormattingModel {
-    private val documentModel = FormattingDocumentModelImpl.createOn(file)
+    private val documentModel = FormattingDocumentModelImpl(DocumentImpl(file.viewProvider.contents, true), file)
     private val changes = HashSet<FormattingChange>()
 
     val requestedChanges: Set<FormattingChange> get() = changes