JVM_IR: fold inline lambdas when computing OUTERCLASS

so that the enclosing method of objects defined inside lambdas is the
one they are declared in.

Note that this does not fix *all* enclosingInfo tests because JVM_IR
currently follows the KT-28064 proposal, i.e. does not regenerate
objects defined inside lambdas under any circumstances. For example,
this causes test boxInline/enclosingInfo/inlineChain2.kt to fail because
the enclosing method of objects is _2Kt.box instead of (non-existent in
source code) `_2Kt$box$inlined$call$1.invoke` or whatever. What's more
important is that OUTERCLASS no longer points to a non-existent
`box$lambda-N` and therefore `.enclosingMethod` no longer throws.

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/ClassCodegen.kt

@@ -52,6 +52,7 @@ open class ClassCodegen protected constructor(
     internal val irClass: IrClass,
     val context: JvmBackendContext,
     private val parentClassCodegen: ClassCodegen? = null,
+    private val parentFunction: IrFunction? = null,
     private val withinInline: Boolean = false
 ) : InnerClassConsumer {
     private val innerClasses = mutableListOf<IrClass>()
@@ -303,8 +304,8 @@ open class ClassCodegen protected constructor(
         }
     }
 
-    fun generateLocalClass(klass: IrClass, withinInline: Boolean): ReifiedTypeParametersUsages {
-        return ClassCodegen(klass, context, this, withinInline = withinInline || this.withinInline).generate()
+    fun generateLocalClass(klass: IrClass, parentFunction: IrFunction): ReifiedTypeParametersUsages {
+        return ClassCodegen(klass, context, this, parentFunction, withinInline = withinInline || parentFunction.isInline).generate()
     }
 
     private fun generateField(field: IrField) {
@@ -404,12 +405,9 @@ open class ClassCodegen protected constructor(
         // or constructor, the name and type of the function is recorded as well.
         if (parentClassCodegen != null) {
             val outerClassName = parentClassCodegen.type.internalName
-            // TODO: Since the class could have been reparented in lowerings, this could
-            // be a class instead of the actual function that the class is nested inside
-            // in the source.
-            val containingDeclaration = irClass.symbol.owner.parent
-            if (containingDeclaration is IrFunction) {
-                val method = methodSignatureMapper.mapAsmMethod(containingDeclaration)
+            // TODO: LocalDeclarationsLowering could have moved this class out of its enclosing method.
+            if (parentFunction != null) {
+                val method = methodSignatureMapper.mapAsmMethod(parentFunction)
                 visitor.visitOuterClass(outerClassName, method.name, method.descriptor)
             } else if (irClass.isAnonymousObject) {
                 visitor.visitOuterClass(outerClassName, null, null)

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/ExpressionCodegen.kt

@@ -556,7 +556,7 @@ class ExpressionCodegen(
         )
 
     override fun visitClass(declaration: IrClass, data: BlockInfo): PromisedValue {
-        classCodegen.generateLocalClass(declaration, generateSequence(this) { it.inlinedInto }.any { it.irFunction.isInline }).also {
+        classCodegen.generateLocalClass(declaration, generateSequence(this) { it.inlinedInto }.last().irFunction).also {
             closureReifiedMarkers[declaration] = it
         }
         return immaterialUnitValue

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/codegen/IrSourceCompilerForInline.kt

@@ -58,11 +58,11 @@ class IrSourceCompilerForInline(
 
     override val inlineCallSiteInfo: InlineCallSiteInfo
         get() {
-            //TODO: support nested inline calls
+            val root = generateSequence(codegen) { it.inlinedInto }.last()
             return InlineCallSiteInfo(
-                codegen.classCodegen.type.internalName,
-                codegen.signature.asmMethod.name,
-                codegen.signature.asmMethod.descriptor,
+                root.classCodegen.type.internalName,
+                root.signature.asmMethod.name,
+                root.signature.asmMethod.descriptor,
                 //compilationContextFunctionDescriptor.isInlineOrInsideInline()
                 false,
                 compilationContextFunctionDescriptor.isSuspend

compiler/testData/codegen/box/reflection/enclosing/kt6368.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 
 // WITH_REFLECT

compiler/testData/codegen/boxInline/enclosingInfo/anonymousInLambda.kt

@@ -1,5 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
-// IGNORE_BACKEND_MULTI_MODULE: JVM_IR
 // TARGET_BACKEND: JVM
 // NO_CHECK_LAMBDA_INLINING
 // WITH_REFLECT

compiler/testData/codegen/boxInline/enclosingInfo/inlineChain.kt

@@ -1,5 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
-// IGNORE_BACKEND_MULTI_MODULE: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: 1.kt
 // WITH_REFLECT

compiler/testData/codegen/boxInline/signature/typeParameterInLambda.kt

@@ -1,5 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
-// IGNORE_BACKEND_MULTI_MODULE: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: 1.kt
 // WITH_REFLECT