cleanup: remove 'public' modifier from constructors in non-public classes (IDEA-195931)

public constructors in non-public classes may be confusing, and removing them makes code shorter.

src/org/jetbrains/java/decompiler/main/rels/NestedClassProcessor.java

@@ -902,7 +902,7 @@ public class NestedClassProcessor {
     public String fieldKey;
     public VarVersionPair varPair;
 
-    public VarFieldPair(String field, VarVersionPair varPair) {
+    VarFieldPair(String field, VarVersionPair varPair) {
       this.fieldKey = field;
       this.varPair = varPair;
     }