JetDiagnosticsTest migrated to TestGenerator

- test data files renamed from *.jet to *.kt

compiler/testData/diagnostics/tests/extensions/kt819ExtensionProperties.kt

@@ -0,0 +1,33 @@
+
+//KT-819 Redeclaration error for extension properties with the same name and different receivers
+
+import java.io.*
+
+inline val InputStream.buffered : BufferedInputStream
+    get() = if(this is BufferedInputStream) this else BufferedInputStream(this)
+
+inline val Reader.buffered : BufferedReader
+    get() = if(this is BufferedReader) this else BufferedReader(this)
+
+
+//more tests
+open class A() {
+    open fun String.foo() {}
+    open fun Int.foo() {}
+
+    open val String.foo = 0
+    open val Int.foo = 1
+}
+
+class B() : A() {
+    override fun String.foo() {}
+    override fun Int.foo() {}
+
+    override val String.foo = 0
+    override val Int.foo = 0
+
+    fun use(s: String) {
+        s.foo
+        s.foo()
+    }
+}