TypeSystemContext: Rework raw types processing

All the current usages are about checking if the type is raw,
also in K2 it is simply incorrect to assume that only flexible types
might be raw

compiler/fir/providers/src/org/jetbrains/kotlin/fir/types/ConeTypeContext.kt

@@ -113,9 +113,9 @@ interface ConeTypeContext : TypeSystemContext, TypeSystemOptimizationContext, Ty
         return this as? ConeDynamicType
     }
 
-    override fun FlexibleTypeMarker.asRawType(): RawTypeMarker? {
-        require(this is ConeFlexibleType)
-        return this as? ConeRawType
+    override fun KotlinTypeMarker.isRawType(): Boolean {
+        require(this is ConeKotlinType)
+        return this.isRaw()
     }
 
     override fun FlexibleTypeMarker.upperBound(): SimpleTypeMarker {

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/IrTypeSystemContext.kt

@@ -54,7 +54,7 @@ interface IrTypeSystemContext : TypeSystemContext, TypeSystemCommonSuperTypesCon
 
     override fun FlexibleTypeMarker.asDynamicType() = this as? IrDynamicType
 
-    override fun FlexibleTypeMarker.asRawType(): RawTypeMarker? = null
+    override fun KotlinTypeMarker.isRawType(): Boolean = false
 
     override fun FlexibleTypeMarker.upperBound(): SimpleTypeMarker {
         return when (this) {

compiler/resolution.common/src/org/jetbrains/kotlin/types/AbstractTypeApproximator.kt

@@ -118,7 +118,7 @@ abstract class AbstractTypeApproximator(
             is FlexibleTypeMarker -> {
                 if (type.isDynamic()) {
                     return if (conf.dynamic) null else type.bound()
-                } else if (type.asRawType() != null) {
+                } else if (type.isRawType()) {
                     return if (conf.rawType) null else type.bound()
                 }
 

core/compiler.common.jvm/src/org/jetbrains/kotlin/load/java/typeEnhancement/AbstractSignatureParts.kt

@@ -204,7 +204,7 @@ abstract class AbstractSignatureParts<TAnnotation : Any> {
     private fun KotlinTypeMarker.toIndexed(): List<TypeAndDefaultQualifiers> = with(typeSystem) {
         TypeAndDefaultQualifiers(this@toIndexed, extractAndMergeDefaultQualifiers(containerDefaultTypeQualifiers), null).flattenTree {
             // Enhancement of raw type arguments may enter a loop in FE1.0.
-            if (skipRawTypeArguments && it.type?.asFlexibleType()?.asRawType() != null) return@flattenTree null
+            if (skipRawTypeArguments && it.type?.isRawType() == true) return@flattenTree null
 
             it.type?.typeConstructor()?.getParameters()?.zip(it.type.getArguments()) { parameter, arg ->
                 if (arg.isStarProjection()) {

core/compiler.common/src/org/jetbrains/kotlin/types/TypeSystemCommonBackendContext.kt

@@ -62,8 +62,6 @@ interface TypeSystemCommonBackendContextForTypeMapping : TypeSystemCommonBackend
     fun SimpleTypeMarker.isSuspendFunction(): Boolean
     fun SimpleTypeMarker.isKClass(): Boolean
 
-    fun KotlinTypeMarker.isRawType(): Boolean
-
     fun TypeConstructorMarker.typeWithArguments(arguments: List<KotlinTypeMarker>): SimpleTypeMarker
     fun TypeConstructorMarker.typeWithArguments(vararg arguments: KotlinTypeMarker): SimpleTypeMarker {
         return typeWithArguments(arguments.toList())

core/compiler.common/src/org/jetbrains/kotlin/types/model/TypeSystemContext.kt

@@ -356,7 +356,7 @@ interface TypeSystemContext : TypeSystemOptimizationContext {
     fun KotlinTypeMarker.isUninferredParameter(): Boolean
     fun FlexibleTypeMarker.asDynamicType(): DynamicTypeMarker?
 
-    fun FlexibleTypeMarker.asRawType(): RawTypeMarker?
+    fun KotlinTypeMarker.isRawType(): Boolean
     fun FlexibleTypeMarker.upperBound(): SimpleTypeMarker
 
     fun FlexibleTypeMarker.lowerBound(): SimpleTypeMarker

core/descriptors/src/org/jetbrains/kotlin/types/checker/ClassicTypeSystemContext.kt

@@ -153,9 +153,9 @@ interface ClassicTypeSystemContext : TypeSystemInferenceExtensionContext, TypeSy
         return this as? DynamicType
     }
 
-    override fun FlexibleTypeMarker.asRawType(): RawTypeMarker? {
-        require(this is FlexibleType, this::errorMessage)
-        return this as? RawType
+    override fun KotlinTypeMarker.isRawType(): Boolean {
+        require(this is KotlinType, this::errorMessage)
+        return this is RawType
     }
 
     override fun FlexibleTypeMarker.upperBound(): SimpleTypeMarker {