code cleanup: rest of small modules under 'idea'

idea/idea-core/src/org/jetbrains/kotlin/idea/core/OptionalParametersHelper.kt

@@ -22,12 +22,10 @@ import org.jetbrains.kotlin.descriptors.CallableDescriptor
 import org.jetbrains.kotlin.descriptors.ValueParameterDescriptor
 import org.jetbrains.kotlin.idea.caches.resolve.analyze
 import org.jetbrains.kotlin.idea.codeInsight.DescriptorToSourceUtilsIde
-import org.jetbrains.kotlin.idea.decompiler.navigation.JetSourceNavigationHelper
 import org.jetbrains.kotlin.psi.JetExpression
 import org.jetbrains.kotlin.psi.JetParameter
 import org.jetbrains.kotlin.psi.JetSimpleNameExpression
 import org.jetbrains.kotlin.psi.ValueArgument
-import org.jetbrains.kotlin.idea.core.copied
 import org.jetbrains.kotlin.psi.psiUtil.forEachDescendantOfType
 import org.jetbrains.kotlin.resolve.BindingContext
 import org.jetbrains.kotlin.resolve.calls.callUtil.getParameterForArgument
@@ -130,7 +128,7 @@ public object OptionalParametersHelper {
         val declaration = DescriptorToSourceUtilsIde.getAnyDeclaration(project, parameter)?.getNavigationElement() as? JetParameter
         val expression = declaration?.getDefaultValue() ?: return null
 
-        val allParameters = (parameter.getContainingDeclaration() as CallableDescriptor).getValueParameters().toSet()
+        val allParameters = parameter.getContainingDeclaration().getValueParameters().toSet()
 
         val parameterUsages = HashMap<ValueParameterDescriptor, MutableCollection<JetExpression>>()
 

idea/idea-core/src/org/jetbrains/kotlin/idea/core/codeInsight/OverrideImplementMethodsHandler.kt

@@ -152,7 +152,7 @@ public abstract class OverrideImplementMethodsHandler : LanguageCodeInsightActio
 
                 val elementsToCompact = ArrayList<JetElement>()
                 for (element in generateOverridingMembers(selectedElements, classOrObject)) {
-                    val added = body!!.addAfter(element, afterAnchor)
+                    val added = body.addAfter(element, afterAnchor)
 
                     if (firstGenerated == null) {
                         firstGenerated = added

idea/idea-core/src/org/jetbrains/kotlin/idea/core/psiFilters.kt

@@ -27,10 +27,10 @@ public class FirstChildInParentFilter(val level: Int = 1) : PositionElementFilte
         var parent: PsiElement? = element
         for (i in 1..level) {
             if (parent == null) break
-            parent = parent?.getContext()
+            parent = parent.getContext()
         }
 
-        return (parent != null) && PsiTreeUtil.isAncestor(parent?.getFirstChild(), element, true)
+        return (parent != null) && PsiTreeUtil.isAncestor(parent.getFirstChild(), element, true)
     }