Switch JVM target of the standard libraries to 1.8 #KT-51907

libraries/stdlib/common/build.gradle

@@ -4,7 +4,7 @@ apply plugin: 'kotlin-platform-common'
 
 configurePublishing(project)
 
-JvmToolchain.updateJvmTarget(project, "1.6")
+JvmToolchain.updateJvmTarget(project, "1.8")
 
 def commonSrcDir = "../src"
 def commonTestSrcDir = "../test"

libraries/stdlib/jdk7/build.gradle

@@ -2,8 +2,7 @@ description = 'Kotlin Standard Library JDK 7 extension'
 
 apply plugin: 'kotlin'
 
-JvmToolchain.configureJvmToolchain(project, JdkMajorVersion.JDK_1_7)
-JvmToolchain.updateJvmTarget(project, "1.6")
+JvmToolchain.configureJvmToolchain(project, JdkMajorVersion.JDK_1_8)
 
 configurePublishing(project)
 configureSourcesJar()

libraries/stdlib/jvm-minimal-for-test/build.gradle.kts

@@ -7,7 +7,7 @@ plugins {
     `maven-publish`
 }
 
-project.configureJvmToolchain(JdkMajorVersion.JDK_1_6)
+project.configureJvmToolchain(JdkMajorVersion.JDK_1_8)
 
 val builtins by configurations.creating {
     isCanBeResolved = true

libraries/stdlib/jvm/build.gradle

@@ -4,7 +4,7 @@ apply plugin: 'kotlin-platform-jvm'
 
 archivesBaseName = 'kotlin-stdlib'
 
-JvmToolchain.configureJvmToolchain(project, JdkMajorVersion.JDK_1_6)
+JvmToolchain.configureJvmToolchain(project, JdkMajorVersion.JDK_1_8)
 
 configurePublishing(project)
 configureJavadocJar()