Introduce language version 1.3

compiler/testData/cli/jvm/apiVersionInvalid.out

@@ -1,3 +1,3 @@
 error: unknown API version: 239.42
-Supported API versions: 1.0, 1.1, 1.2 (EXPERIMENTAL)
-COMPILATION_ERROR
+Supported API versions: 1.0, 1.1, 1.2 (EXPERIMENTAL), 1.3 (EXPERIMENTAL)
+COMPILATION_ERROR

compiler/testData/cli/jvm/languageVersionInvalid.out

@@ -1,3 +1,3 @@
 error: unknown language version: 239.42
-Supported language versions: 1.0, 1.1, 1.2 (EXPERIMENTAL)
-COMPILATION_ERROR
+Supported language versions: 1.0, 1.1, 1.2 (EXPERIMENTAL), 1.3 (EXPERIMENTAL)
+COMPILATION_ERROR

compiler/util/src/org/jetbrains/kotlin/config/ApiVersion.kt

@@ -50,6 +50,9 @@ class ApiVersion private constructor(
         @JvmField
         val KOTLIN_1_2 = createByLanguageVersion(LanguageVersion.KOTLIN_1_2)
 
+        @JvmField
+        val KOTLIN_1_3 = createByLanguageVersion(LanguageVersion.KOTLIN_1_3)
+
         @JvmField
         val LATEST_STABLE: ApiVersion = createByLanguageVersion(LanguageVersion.LATEST_STABLE)
 

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -16,8 +16,7 @@
 
 package org.jetbrains.kotlin.config
 
-import org.jetbrains.kotlin.config.LanguageVersion.KOTLIN_1_1
-import org.jetbrains.kotlin.config.LanguageVersion.KOTLIN_1_2
+import org.jetbrains.kotlin.config.LanguageVersion.*
 import org.jetbrains.kotlin.utils.DescriptionAware
 import java.util.*
 
@@ -91,7 +90,8 @@ enum class LanguageFeature(
 enum class LanguageVersion(val major: Int, val minor: Int) : DescriptionAware {
     KOTLIN_1_0(1, 0),
     KOTLIN_1_1(1, 1),
-    KOTLIN_1_2(1, 2);
+    KOTLIN_1_2(1, 2),
+    KOTLIN_1_3(1, 3);
 
     val isStable: Boolean
         get() = this <= LATEST_STABLE