Enable full highlighting in script files everywhere (was inside source roots only)

Extract KotlinHighlightingUtil to hold this logic

idea/idea-analysis/src/org/jetbrains/kotlin/idea/highlighter/KotlinHighlightingUtil.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * 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.highlighter
+
+import com.intellij.psi.PsiElement
+import org.jetbrains.kotlin.idea.util.ProjectRootsUtil
+import org.jetbrains.kotlin.psi.KtCodeFragment
+import org.jetbrains.kotlin.psi.KtFile
+
+object KotlinHighlightingUtil {
+    fun shouldHighlight(psiElement: PsiElement): Boolean {
+        val ktFile = psiElement.containingFile as? KtFile ?: return false
+        return ktFile is KtCodeFragment || ktFile.isScript || ProjectRootsUtil.isInProjectOrLibraryContent(ktFile)
+    }
+
+    fun shouldHighlightErrors(psiElement: PsiElement): Boolean {
+        val ktFile = psiElement.containingFile as? KtFile ?: return false
+        return ktFile is KtCodeFragment || ktFile.isScript || ProjectRootsUtil.isInProjectSource(ktFile)
+    }
+}

idea/idea-analysis/src/org/jetbrains/kotlin/idea/highlighter/KotlinProblemHighlightFilter.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,12 +19,12 @@ package org.jetbrains.kotlin.idea.highlighter
 import com.intellij.codeInsight.daemon.ProblemHighlightFilter
 import com.intellij.psi.PsiFile
 import org.jetbrains.kotlin.idea.KotlinFileType
-import com.intellij.ide.projectView.impl.ProjectRootsUtil
 
 class KotlinProblemHighlightFilter : ProblemHighlightFilter() {
 
     override fun shouldHighlight(psiFile: PsiFile): Boolean {
-        return psiFile.fileType != KotlinFileType.INSTANCE || !ProjectRootsUtil.isOutsideSourceRoot(psiFile)
+        if (psiFile.fileType == KotlinFileType.INSTANCE && !KotlinHighlightingUtil.shouldHighlight(psiFile)) return false
-    }
 
+        return true
+    }
 }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/highlighter/KotlinPsiChecker.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -56,9 +56,9 @@ import java.util.*
 open class KotlinPsiChecker : Annotator, HighlightRangeExtension {
 
     override fun annotate(element: PsiElement, holder: AnnotationHolder) {
-        if (!(ProjectRootsUtil.isInProjectOrLibraryContent(element) || element.containingFile is KtCodeFragment)) return
+        val file = element.containingFile as? KtFile ?: return
 
-        val file = element.containingFile as KtFile
+        if (!KotlinHighlightingUtil.shouldHighlight(file)) return
 
         val analysisResult = file.analyzeFullyAndGetResult()
         if (analysisResult.isError()) {
@@ -88,7 +88,7 @@ open class KotlinPsiChecker : Annotator, HighlightRangeExtension {
 
         if (diagnosticsForElement.isEmpty()) return
 
-        if (ProjectRootsUtil.isInProjectSource(element) || element.containingFile is KtCodeFragment) {
+        if (KotlinHighlightingUtil.shouldHighlightErrors(element)) {
             ElementAnnotator(element, holder, { param -> shouldSuppressUnusedParameter(param) }).registerDiagnosticsAnnotations(diagnosticsForElement)
         }
     }