Added test with @KotlinSignature on method returning array.

#KT-2840 can't reproduce

compiler/testData/loadJava/kotlinSignature/ArrayType.java

@@ -0,0 +1,10 @@
+package test;
+
+import jet.runtime.typeinfo.KotlinSignature;
+
+public class ArrayType {
+    @KotlinSignature("fun foo(): Array<String>")
+    public String[] foo() {
+        throw new UnsupportedOperationException();
+    }
+}

compiler/testData/loadJava/kotlinSignature/ArrayType.kt

@@ -0,0 +1,7 @@
+package test
+
+public open class ArrayType : Object() {
+    public open fun foo(): Array<String> {
+        throw UnsupportedOperationException()
+    }
+}

compiler/testData/loadJava/kotlinSignature/ArrayType.txt

@@ -0,0 +1,6 @@
+namespace test
+
+public open class test.ArrayType : java.lang.Object {
+    public final /*constructor*/ fun <init>(): test.ArrayType
+    public open fun foo(): jet.Array<jet.String>
+}