AbstractStringBuilder, StringBuilder and java.io.File annotated with nullable/notnull

libraries/stdlib/src/kotlin/io/Files.kt

@@ -207,6 +207,6 @@ fun File.readLines(charset : String = "UTF-8") : List<String> {
  */
 fun File.listFiles(filter : (file : File) -> Boolean) : Array<File>? = listFiles(
     object : FileFilter {
-        override fun accept(file: File?) = filter(file!!)
+        override fun accept(file: File) = filter(file)
     }
 ) as Array<File>?

libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/highlighter2/Html2CompilerPlugin.kt

@@ -35,7 +35,7 @@ class Html2CompilerPlugin(private val compilerArguments: KDocArguments) : Doclet
     private val sourceDirPaths: List<String> = sourceDirs.map { d -> d.getPath()!! }
 
     private fun fileToWrite(psiFile: PsiFile): String {
-        val file = File((psiFile.getVirtualFile() as CoreLocalVirtualFile).getPath()).getCanonicalFile()!!
+        val file = File((psiFile.getVirtualFile() as CoreLocalVirtualFile).getPath()!!).getCanonicalFile()!!
         val filePath = file.getPath()!!
         for (sourceDirPath in sourceDirPaths) {
             if (filePath.startsWith(sourceDirPath) && filePath.length() > sourceDirPath.length()) {

libraries/tools/kdoc/src/main/kotlin/org/jetbrains/kotlin/doc/model/KotlinModel.kt

@@ -212,7 +212,7 @@ class KModel(val context: BindingContext, val config: KDocConfig, val sourceDirs
         sourceDirs.map { file -> file.getCanonicalPath()!! }
 
         fun relativePath(psiFile: PsiFile): String {
-            val file = File((psiFile.getVirtualFile() as CoreLocalVirtualFile).getPath()).getCanonicalFile()!!
+            val file = File((psiFile.getVirtualFile() as CoreLocalVirtualFile).getPath()!!).getCanonicalFile()!!
             val filePath = file.getPath()!!
             for (sourceDirPath in normalizedSourceDirs) {
                 if (filePath.startsWith(sourceDirPath) && filePath.length() > sourceDirPath.length()) {