Better validity check for kotlin light element

There're exceptions from `isWritable` method in light classes caused by
accessing invalid elements.

Override KtLightMemberImpl implementation to avoid activating
decompiler during validity check.

compiler/light-classes/src/org/jetbrains/kotlin/asJava/builder/LightElementOrigin.kt

@@ -53,6 +53,7 @@ interface LightMemberOrigin : LightElementOrigin {
     val parametersForJvmOverloads: List<KtParameter?>? get() = null
     val auxiliaryOriginalElement: KtDeclaration? get() = null
 
+    fun isValid(): Boolean
     fun isEquivalentTo(other: LightMemberOrigin?): Boolean
     fun copy(): LightMemberOrigin
 }
@@ -63,6 +64,8 @@ data class LightMemberOriginForDeclaration(
     override val parametersForJvmOverloads: List<KtParameter?>? = null,
     override val auxiliaryOriginalElement: KtDeclaration? = null
 ) : LightMemberOrigin {
+    override fun isValid(): Boolean = originalElement.isValid
+
     override fun isEquivalentTo(other: LightMemberOrigin?): Boolean {
         if (other !is LightMemberOriginForDeclaration) return false
         return originalElement.isEquivalentTo(other.originalElement)

compiler/light-classes/src/org/jetbrains/kotlin/asJava/elements/KtLightElementBase.kt

@@ -38,7 +38,7 @@ abstract class KtLightElementBase(private val parent: PsiElement): LightElement(
     override fun getUseScope() = kotlinOrigin?.useScope ?: super.getUseScope()
     override fun getContainingFile() = parent.containingFile
     override fun getPresentation() = (kotlinOrigin ?: this).let { ItemPresentationProviders.getItemPresentation(it) }
-    override fun isValid() = parent.isValid
+    override fun isValid() = parent.isValid && (kotlinOrigin?.isValid != false)
     override fun findElementAt(offset: Int) = kotlinOrigin?.findElementAt(offset)
     override fun isEquivalentTo(another: PsiElement?): Boolean =
         super.isEquivalentTo(another) || kotlinOrigin?.isEquivalentTo(another) == true

compiler/light-classes/src/org/jetbrains/kotlin/asJava/elements/KtLightMemberImpl.kt

@@ -65,6 +65,10 @@ abstract class KtLightMemberImpl<out D : PsiMember>(
 
     override fun isDeprecated() = (clsDelegate as PsiDocCommentOwner).isDeprecated
 
+    override fun isValid(): Boolean {
+        return parent.isValid && lightMemberOrigin?.isValid() != false
+    }
+
     override fun isEquivalentTo(another: PsiElement?): Boolean {
         if (lightMemberOrigin?.originalElement?.isEquivalentTo(another) == true) return true