Move the JUnitBootstrappers phase to transform.sjs.

Since it is in fact a transformation, not a back-end thing.

Author: sjrd

compiler/src/dotty/tools/dotc/Compiler.scala

@@ -122,7 +122,7 @@ class Compiler {
          new ExpandPrivate,          // Widen private definitions accessed from nested classes
          new RestoreScopes,          // Repair scopes rendered invalid by moving definitions in prior phases of the group
          new SelectStatic,           // get rid of selects that would be compiled into GetStatic
-         new backend.sjs.JUnitBootstrappers, // Generate JUnit-specific bootstrapper classes for Scala.js (not enabled by default)
+         new sjs.JUnitBootstrappers, // Generate JUnit-specific bootstrapper classes for Scala.js (not enabled by default)
          new CollectSuperCalls) ::   // Find classes that are called with super
     Nil
 

compiler/src/dotty/tools/backend/sjs/JUnitBootstrappers.scala renamed to compiler/src/dotty/tools/dotc/transform/sjs/JUnitBootstrappers.scala

@@ -1,9 +1,9 @@
-package dotty.tools.backend.sjs
+package dotty.tools.dotc
+package transform
+package sjs
 
 import scala.annotation.tailrec
 
-import dotty.tools.dotc._
-
 import dotty.tools.dotc.core._
 import Constants._
 import Contexts._
@@ -19,6 +19,8 @@ import Types._
 
 import dotty.tools.dotc.transform.MegaPhase._
 
+import dotty.tools.backend.sjs.JSDefinitions.jsdefn
+
 /** Generates JUnit bootstrapper objects for Scala.js.
  *
  *  On the JVM, JUnit uses run-time reflection to list and invoke JUnit-related
@@ -108,7 +110,6 @@ import dotty.tools.dotc.transform.MegaPhase._
 class JUnitBootstrappers extends MiniPhase {
   import JUnitBootstrappers._
   import ast.tpd._
-  import JSDefinitions.jsdefn
 
   def phaseName: String = "junitBootstrappers"