Minor, convert CommonConfigurationKeys to Kotlin

compiler/frontend/src/org/jetbrains/kotlin/config/CommonConfigurationKeys.java

@@ -1,34 +0,0 @@
-/*
- * Copyright 2010-2015 JetBrains s.r.o.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.jetbrains.kotlin.config;
-
-public class CommonConfigurationKeys {
-    private CommonConfigurationKeys() {
-    }
-
-    public static final CompilerConfigurationKey<LanguageVersionSettings> LANGUAGE_VERSION_SETTINGS =
-            CompilerConfigurationKey.create("language version settings");
-
-    public static final CompilerConfigurationKey<Boolean> SKIP_METADATA_VERSION_CHECK =
-            CompilerConfigurationKey.create("skip metadata version check");
-
-    public static final CompilerConfigurationKey<Boolean> DISABLE_INLINE =
-            CompilerConfigurationKey.create("disable inline");
-
-    public static final CompilerConfigurationKey<String> MODULE_NAME =
-            CompilerConfigurationKey.create("module name");
-}

compiler/frontend/src/org/jetbrains/kotlin/config/CommonConfigurationKeys.kt

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2010-2015 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.config
+
+object CommonConfigurationKeys {
+    @JvmField
+    val LANGUAGE_VERSION_SETTINGS = CompilerConfigurationKey<LanguageVersionSettings>("language version settings")
+
+    @JvmField
+    val SKIP_METADATA_VERSION_CHECK = CompilerConfigurationKey<Boolean>("skip metadata version check")
+
+    @JvmField
+    val DISABLE_INLINE = CompilerConfigurationKey<Boolean>("disable inline")
+
+    @JvmField
+    val MODULE_NAME = CompilerConfigurationKey<String>("module name")
+}

compiler/frontend/src/org/jetbrains/kotlin/config/CompilerConfigurationKey.java

@@ -23,10 +23,11 @@ import org.jetbrains.annotations.NotNull;
 public class CompilerConfigurationKey<T> {
     Key<T> ideaKey;
 
-    private CompilerConfigurationKey(@NotNull @NonNls String name) {
+    public CompilerConfigurationKey(@NotNull @NonNls String name) {
         ideaKey = Key.create(name);
     }
 
+    @NotNull
     public static <T> CompilerConfigurationKey<T> create(@NotNull @NonNls String name) {
         return new CompilerConfigurationKey<T>(name);
     }