[EE-IR] Use reflection to avoid the need for accessors when compiling

evaluator fragments

- Refactor JvmIrCodegenFactory to allow for caller's choice of
  lowerings.

- Refactor of SyntheticAccessorLowering to expose the accessibility
  check used to determine the need for accessors.

- Replacement of field, method and constructor uses with corresponding
  java.lang.reflection API via additional lowering running _before_
  the existing IR pipeline.

- Emulating super calls in the context of class methods via new
  compiler intrinsic.

- psi2ir: Add support for `_field` suffix on properties in the
  evaluator for accessing underlying fields when applicable.

- Add `JvmGeneratorExtensions` point for determining whether a
  property accessor has a user-supplied body in order to predict how
  they are ultimately compiled for the JVM.

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrStatementOrigin.kt

@@ -121,3 +121,14 @@ fun IrStatementOrigin.isAssignmentOperatorWithResult() =
         else ->
             false
     }
+
+fun IrStatementOrigin.isAssignmentOperator(): Boolean =
+    when (this) {
+        IrStatementOrigin.EQ,
+        IrStatementOrigin.PLUSEQ,
+        IrStatementOrigin.MINUSEQ,
+        IrStatementOrigin.MULTEQ,
+        IrStatementOrigin.DIVEQ,
+        IrStatementOrigin.PERCEQ -> true
+        else -> isAssignmentOperatorWithResult()
+    }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/StubGeneratorExtensions.kt

@@ -9,7 +9,6 @@ import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
 import org.jetbrains.kotlin.descriptors.FunctionDescriptor
 import org.jetbrains.kotlin.descriptors.PropertyDescriptor
 import org.jetbrains.kotlin.ir.declarations.*
-import org.jetbrains.kotlin.ir.declarations.lazy.IrLazyClass
 import org.jetbrains.kotlin.serialization.deserialization.descriptors.DeserializedContainerSource
 import org.jetbrains.kotlin.types.KotlinType
 
@@ -35,6 +34,15 @@ open class StubGeneratorExtensions {
     // intercept and supply "fake" deserialized sources.
     open fun getContainerSource(descriptor: DeclarationDescriptor): DeserializedContainerSource? = null
 
+    // Extension point for the JVM Debugger IDEA plug-in: to replace accesses
+    // to private properties _without_ accessor implementations, the fragment
+    // compiler needs to predict the compilation output for properties.
+    // To do this, we need to know whether the property accessors have explicit
+    // bodies, information that is _not_ present in the IR structure, but _is_
+    // available in the corresponding PSI. See `CodeFragmentCompiler` in the
+    // plug-in for the implementation.
+    open fun isAccessorWithExplicitImplementation(accessor: IrSimpleFunction): Boolean = false
+
     open fun isPropertyWithPlatformField(descriptor: PropertyDescriptor): Boolean = false
 
     open fun isStaticFunction(descriptor: FunctionDescriptor): Boolean = false