items that are prefixes of other items should go first

Java expected type also should go first, and win
current class should be preferred in completion (IDEA-64703)

java/java-tests/testData/codeInsight/completion/style/after15.java

@@ -1,6 +1,6 @@
 class A{
 {
  String str;
- str.toString();
+ str.toCharArray();
  }
 }

java/java-tests/testData/codeInsight/completion/style/after17.java

@@ -1,7 +1,7 @@
 class A{
  {
   final String path = BASE_PATH;
-  path.toString()<caret>;
+  path.toCharArray()<caret>;
   sdkfjsdkhjfh();
  }
 }