IR: rename DeclarationFactory to InnerClassesSupport, move out of context

Methods of the common interface DeclarationFactory were only used in
lowerings in InnerClassesLowering, which were used in JVM and JS, not
Native. Therefore, it makes sense to have this as a separate interface
and pass its implementation to these lowerings directly, instead of
declaring it in the common context (which is not going to be implemented
in Native).

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsIrBackendContext.kt

@@ -8,7 +8,7 @@ package org.jetbrains.kotlin.ir.backend.js
 import org.jetbrains.kotlin.backend.common.atMostOne
 import org.jetbrains.kotlin.backend.common.ir.Ir
 import org.jetbrains.kotlin.backend.common.ir.Symbols
-import org.jetbrains.kotlin.backend.js.JsDeclarationFactory
+import org.jetbrains.kotlin.ir.backend.js.lower.JsInnerClassesSupport
 import org.jetbrains.kotlin.builtins.PrimitiveType
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.descriptors.*
@@ -134,7 +134,7 @@ class JsIrBackendContext(
         get() = testContainerFuns
 
     override val mapping = JsMapping()
-    override val declarationFactory = JsDeclarationFactory(mapping)
+    val innerClassesSupport = JsInnerClassesSupport(mapping)
 
     companion object {
         val KOTLIN_PACKAGE_FQN = FqName.fromSegments(listOf("kotlin"))

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/JsLoweringPhases.kt

@@ -375,20 +375,20 @@ private val localClassExtractionPhase = makeBodyLoweringPhase(
 )
 
 private val innerClassesLoweringPhase = makeDeclarationTransformerPhase(
-    ::InnerClassesLowering,
+    { context -> InnerClassesLowering(context, context.innerClassesSupport) },
     name = "InnerClassesLowering",
     description = "Capture outer this reference to inner class"
 )
 
 private val innerClassesMemberBodyLoweringPhase = makeBodyLoweringPhase(
-    ::InnerClassesMemberBodyLowering,
+    { context -> InnerClassesMemberBodyLowering(context, context.innerClassesSupport) },
     name = "InnerClassesMemberBody",
     description = "Replace `this` with 'outer this' field references",
     prerequisite = setOf(innerClassesLoweringPhase)
 )
 
 private val innerClassConstructorCallsLoweringPhase = makeBodyLoweringPhase(
-    ::InnerClassConstructorCallsLowering,
+    { context -> InnerClassConstructorCallsLowering(context, context.innerClassesSupport) },
     name = "InnerClassConstructorCallsLowering",
     description = "Replace inner class constructor invocation"
 )

compiler/ir/backend.js/src/org/jetbrains/kotlin/ir/backend/js/lower/JsInnerClassesSupport.kt

@@ -3,10 +3,10 @@
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
-package org.jetbrains.kotlin.backend.js
+package org.jetbrains.kotlin.ir.backend.js.lower
 
 import org.jetbrains.kotlin.backend.common.getOrPut
-import org.jetbrains.kotlin.backend.common.ir.DeclarationFactory
+import org.jetbrains.kotlin.backend.common.lower.InnerClassesSupport
 import org.jetbrains.kotlin.backend.common.ir.copyTo
 import org.jetbrains.kotlin.backend.common.ir.copyTypeParametersFrom
 import org.jetbrains.kotlin.descriptors.Visibilities
@@ -23,7 +23,7 @@ import org.jetbrains.kotlin.ir.util.defaultType
 import org.jetbrains.kotlin.ir.util.dump
 import org.jetbrains.kotlin.name.Name
 
-class JsDeclarationFactory(mapping: JsMapping) : DeclarationFactory {
+class JsInnerClassesSupport(mapping: JsMapping) : InnerClassesSupport {
     private val outerThisFieldSymbols = mapping.outerThisFieldSymbols
     private val innerClassConstructors = mapping.innerClassConstructors
     private val originalInnerClassPrimaryConstructorByClass = mapping.originalInnerClassPrimaryConstructorByClass
@@ -36,7 +36,7 @@ class JsDeclarationFactory(mapping: JsMapping) : DeclarationFactory {
                     ?: throw AssertionError("No containing class for inner class ${innerClass.dump()}")
 
                 buildField {
-                    origin = DeclarationFactory.FIELD_FOR_OUTER_THIS
+                    origin = InnerClassesSupport.FIELD_FOR_OUTER_THIS
                     name = Name.identifier("\$this")
                     type = outerClass.defaultType
                     visibility = Visibilities.PROTECTED