Added tests for compiling Java against TraitImpl and extension members.

compiler/testData/compileJavaAgainstKotlin/property/Extensions.java

@@ -0,0 +1,10 @@
+package test;
+
+class GenericArray {
+    {
+        TestPackage.getVal_("");
+
+        TestPackage.getVar_("");
+        TestPackage.setVar_("", "");
+    }
+}

compiler/testData/compileJavaAgainstKotlin/property/Extensions.kt

@@ -0,0 +1,9 @@
+package test
+
+val String.val_: String
+    get() = ""
+
+var String.var_: String
+    get() = ""
+    set(value) {
+    }