Fix windows bootstrap

Author: liufengyun

Diff for: compiler/src/dotty/tools/dotc/classpath/ClassPath.scala

@@ -24,7 +24,7 @@ trait SourceFileEntry extends ClassRepresentation {
 
 case class PackageName(dottedString: String) {
   def isRoot: Boolean = dottedString.isEmpty
-  val dirPathTrailingSlash: String = FileUtils.dirPath(dottedString) + "/"
+  val dirPathTrailingSlash: String = FileUtils.dirPathInArchive(dottedString) + "/"
 
   def entryName(entry: String): String = {
     if (isRoot) entry else {

Diff for: compiler/src/dotty/tools/dotc/classpath/FileUtils.scala

@@ -44,6 +44,8 @@ object FileUtils {
 
   def dirPath(forPackage: String): String = forPackage.replace('.', JFile.separatorChar)
 
+  def dirPathInArchive(forPackage: String): String = forPackage.replace('.', '/')
+
   def endsClass(fileName: String): Boolean =
     fileName.length > 6 && fileName.substring(fileName.length - 6) == ".class"
 

Diff for: compiler/src/dotty/tools/dotc/core/SymbolLoaders.scala

@@ -209,8 +209,7 @@ object SymbolLoaders {
 
   /** Load contents of a package
    */
-  class PackageLoader(_sourceModule: TermSymbol, classPath: ClassPath)
-      extends SymbolLoader {
+  class PackageLoader(_sourceModule: TermSymbol, classPath: ClassPath) extends SymbolLoader {
     override def sourceFileOrNull: AbstractFile = null
     override def sourceModule(using Context): TermSymbol = _sourceModule
     def description(using Context): String = "package loader " + sourceModule.fullName