Minor: remove warnings caused by ExtensionPointName.create nullability

compiler/frontend/src/org/jetbrains/kotlin/extensions/ProjectExtensionDescriptor.kt

@@ -22,11 +22,11 @@ import com.intellij.openapi.extensions.Extensions
 import com.intellij.openapi.project.Project
 
 open class ProjectExtensionDescriptor<T>(name: String, private val extensionClass: Class<T>) {
-    val extensionPointName: ExtensionPointName<T> = ExtensionPointName.create(name)!!
+    val extensionPointName: ExtensionPointName<T> = ExtensionPointName.create(name)
 
     fun registerExtensionPoint(project: Project) {
         Extensions.getArea(project).registerExtensionPoint(
-                extensionPointName.name!!,
+                extensionPointName.name,
                 extensionClass.name,
                 ExtensionPoint.Kind.INTERFACE
         )
@@ -38,7 +38,7 @@ open class ProjectExtensionDescriptor<T>(name: String, private val extensionClas
 
     fun getInstances(project: Project): List<T> {
         val projectArea = Extensions.getArea(project)
-        if (!projectArea.hasExtensionPoint(extensionPointName.name!!)) return listOf()
+        if (!projectArea.hasExtensionPoint(extensionPointName.name)) return listOf()
 
         return projectArea.getExtensionPoint(extensionPointName).extensions.toList()
     }

idea/idea-analysis/src/org/jetbrains/kotlin/idea/facet/KotlinVersionInfoProvider.kt

@@ -26,7 +26,7 @@ import org.jetbrains.kotlin.config.TargetPlatformKind
 
 interface KotlinVersionInfoProvider {
     companion object {
-        val EP_NAME: ExtensionPointName<KotlinVersionInfoProvider> = ExtensionPointName.create("org.jetbrains.kotlin.versionInfoProvider")!!
+        val EP_NAME: ExtensionPointName<KotlinVersionInfoProvider> = ExtensionPointName.create("org.jetbrains.kotlin.versionInfoProvider")
     }
 
     fun getCompilerVersion(module: Module): String?

idea/src/org/jetbrains/kotlin/idea/facet/KotlinFacetConfigurationExtension.kt

@@ -23,7 +23,7 @@ import com.intellij.openapi.extensions.ExtensionPointName
 
 interface KotlinFacetConfigurationExtension {
     companion object {
-        val EP_NAME: ExtensionPointName<KotlinFacetConfigurationExtension> = ExtensionPointName.create("org.jetbrains.kotlin.facetConfigurationExtension")!!
+        val EP_NAME: ExtensionPointName<KotlinFacetConfigurationExtension> = ExtensionPointName.create("org.jetbrains.kotlin.facetConfigurationExtension")
     }
 
     fun createEditorTabs(editorContext: FacetEditorContext, validatorsManager: FacetValidatorsManager): List<FacetEditorTab>

idea/src/org/jetbrains/kotlin/idea/inspections/gradle/KotlinPlatformGradleDetector.kt

@@ -39,7 +39,7 @@ import com.intellij.openapi.externalSystem.util.ExternalSystemApiUtil
 
 interface KotlinPlatformGradleDetector {
     companion object {
-        val EP_NAME: ExtensionPointName<KotlinPlatformGradleDetector> = ExtensionPointName.create("org.jetbrains.kotlin.platformGradleDetector")!!
+        val EP_NAME: ExtensionPointName<KotlinPlatformGradleDetector> = ExtensionPointName.create("org.jetbrains.kotlin.platformGradleDetector")
     }
 
     fun getResolvedKotlinStdlibVersionByModuleData(moduleData: DataNode<*>, libraryIds: List<String>): String?

idea/src/org/jetbrains/kotlin/plugin/findUsages/handlers/KotlinFindUsagesHandlerDecorator.kt

@@ -22,7 +22,7 @@ import com.intellij.find.findUsages.FindUsagesHandler
 
 interface KotlinFindUsagesHandlerDecorator {
     companion object {
-        val EP_NAME: ExtensionPointName<KotlinFindUsagesHandlerDecorator> = ExtensionPointName.create("org.jetbrains.kotlin.findUsagesHandlerDecorator")!!
+        val EP_NAME: ExtensionPointName<KotlinFindUsagesHandlerDecorator> = ExtensionPointName.create("org.jetbrains.kotlin.findUsagesHandlerDecorator")
     }
 
     fun decorateHandler(element: PsiElement, forHighlightUsages: Boolean, delegate: FindUsagesHandler): FindUsagesHandler