Fix Java6BuiltInsWithJDKMembersTest

After update of the project to JDK 8, the default JDK at java.home is
now JDK 8. However, this test relied on the fact that the default is JDK
6. Pass the path to the JDK 6 explicitly

compiler/tests/org/jetbrains/kotlin/serialization/builtins/AbstractBuiltInsWithJDKMembersTest.kt

@@ -42,7 +42,10 @@ abstract class AbstractBuiltInsWithJDKMembersTest : KotlinTestWithEnvironment()
             })
 
     override fun createEnvironment(): KotlinCoreEnvironment =
-            createEnvironmentWithJdk(ConfigurationKind.JDK_ONLY, TestJdkKind.FULL_JDK)
+            createEnvironmentWithJdk(ConfigurationKind.JDK_ONLY, testJdkKind)
+
+    protected open val testJdkKind: TestJdkKind
+        get() = TestJdkKind.FULL_JDK
 
     protected fun doTest(builtinVersionName: String) {
         val module = JvmResolveUtil.analyze(environment).moduleDescriptor as ModuleDescriptorImpl

compiler/tests/org/jetbrains/kotlin/serialization/builtins/Java6BuiltInsWithJDKMembersTest.kt

@@ -16,7 +16,11 @@
 
 package org.jetbrains.kotlin.serialization.builtins
 
+import org.jetbrains.kotlin.test.TestJdkKind
+
 class Java6BuiltInsWithJDKMembersTest : AbstractBuiltInsWithJDKMembersTest() {
+    override val testJdkKind get() = TestJdkKind.FULL_JDK_6
+
     fun testLoadBuiltIns() {
         doTest("java6")
     }