method return type in not used: fix for literal expressions(IDEA-184798)

java/java-tests/testData/inspection/unusedReturnValue/fromReflection/expected.xml

@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problems/>

java/java-tests/testData/inspection/unusedReturnValue/fromReflection/src/Test.java

@@ -0,0 +1,9 @@
+class Test {
+  static String foo() {
+    return "";
+  }
+
+  {
+    Test.class.getMethod("foo");
+  }
+}