fix Collections.emptyMap not being suggested in completion if jdk8 is used

java/java-tests/testData/codeInsight/completion/smartType/CollectionsEmptyMap-out.java

@@ -0,0 +1,9 @@
+import java.util.Collections;
+import java.util.Map;
+
+class Foo {
+  void m() {
+    Map<String, Integer> m = Collections.emptyMap();<caret>
+  }
+
+}

java/java-tests/testData/codeInsight/completion/smartType/CollectionsEmptyMap.java

@@ -0,0 +1,8 @@
+import java.util.Map;
+
+class Foo {
+  void m() {
+    Map<String, Integer> m = emptyM<caret>
+  }
+
+}