java completion: don't qualify local class fields with "this", cleanup (IDEA-CR-63622)

GitOrigin-RevId: 5dca120cc7b4f82829c9da0be0e409f21993c477

java/java-tests/testData/codeInsight/completion/normal/FieldOfLocalClass.java

@@ -0,0 +1,11 @@
+class C {
+  static void bar() {
+    class Visitor {
+      int field;
+
+      void foo() {
+        fie<caret>x
+      }
+    }
+  }
+}

java/java-tests/testData/codeInsight/completion/normal/FieldOfLocalClass_after.java

@@ -0,0 +1,11 @@
+class C {
+  static void bar() {
+    class Visitor {
+      int field;
+
+      void foo() {
+        field<caret>
+      }
+    }
+  }
+}