Removed useless as casts from compiler code

It allows compiling code with K2 and enabled `-Werror`

analysis/analysis-api-fe10/src/org/jetbrains/kotlin/analysis/api/descriptors/components/KtFe10ExpressionTypeProvider.kt

@@ -300,10 +300,9 @@ class KtFe10ExpressionTypeProvider(
     }
 
     override fun isDefinitelyNotNull(expression: KtExpression): Boolean {
-        val ktExpression = expression as? KtExpression ?: return false
-        val bindingContext = analysisContext.analyze(ktExpression)
+        val bindingContext = analysisContext.analyze(expression)
 
-        val smartCasts = bindingContext[BindingContext.SMARTCAST, ktExpression]
+        val smartCasts = bindingContext[BindingContext.SMARTCAST, expression]
 
         if (smartCasts is MultipleSmartCasts) {
             if (smartCasts.map.values.all { !it.isMarkedNullable }) {

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/symbols/pointers/KtFirMemberSymbolPointer.kt

@@ -13,7 +13,6 @@ import org.jetbrains.kotlin.analysis.api.symbols.markers.KtSymbolWithMembers
 import org.jetbrains.kotlin.analysis.api.symbols.pointers.KtSymbolPointer
 import org.jetbrains.kotlin.analysis.utils.errors.requireIsInstance
 import org.jetbrains.kotlin.fir.FirSession
-import org.jetbrains.kotlin.fir.declarations.FirClass
 import org.jetbrains.kotlin.fir.declarations.FirResolvePhase
 import org.jetbrains.kotlin.fir.scopes.FirScope
 import org.jetbrains.kotlin.fir.scopes.unsubstitutedScope
@@ -42,7 +41,7 @@ internal abstract class KtFirMemberSymbolPointer<S : KtSymbol>(
         val firSession = useSiteSession
         val scopeSession = getScopeSessionFor(firSession)
         return if (isStatic) {
-            val firClass = owner.fir as? FirClass ?: return null
+            val firClass = owner.fir
             firClass.scopeProvider.getStaticMemberScopeForCallables(firClass, firSession, scopeSession)
         } else {
             owner.unsubstitutedScope(

analysis/analysis-api-impl-base/tests/org/jetbrains/kotlin/analysis/api/impl/base/test/cases/components/symbolDeclarationRenderer/AbstractRendererTest.kt

@@ -36,8 +36,7 @@ abstract class AbstractRendererTest : AbstractAnalysisApiSingleFileTest() {
             buildString {
                 ktFile.declarations.forEach { declaration ->
                     analyseForTest(declaration) {
-                        val symbol = declaration.getSymbol() as? KtDeclarationSymbol ?: return@analyseForTest
-                        append(symbol.render(renderer))
+                        append(declaration.getSymbol().render(renderer))
                         appendLine()
                         appendLine()
                     }

analysis/low-level-api-fir/src/org/jetbrains/kotlin/analysis/low/level/api/fir/stubBased/deserialization/StubBasedFirTypeDeserializer.kt

@@ -108,7 +108,7 @@ internal class StubBasedFirTypeDeserializer(
         val annotations = annotationDeserializer.loadAnnotations(typeReference).toMutableList()
         val parent = (typeReference.stub ?: loadStubByElement(typeReference))?.parentStub
         if (parent is KotlinParameterStubImpl) {
-            (parent as? KotlinParameterStubImpl)?.functionTypeParameterName?.let { paramName ->
+            parent.functionTypeParameterName?.let { paramName ->
                 annotations += buildAnnotation {
                     annotationTypeRef = buildResolvedTypeRef {
                         type = StandardNames.FqNames.parameterNameClassId.toLookupTag()