replace type with var: allow anonymous type replacement (IDEA-210534)

though interface to implementation replacement may lead to implementation type propagation, anonymous type can't be propagated so it's safe to be used as var

GitOrigin-RevId: cae306614efcb92551f2aa907f8d66e1bd2db930

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/explicit2var/beforeAnonymous.java

@@ -0,0 +1,9 @@
+// "Replace explicit type with 'var'" "true"
+class MyTest {
+  private void m() {
+    Ru<caret>nnable r = new Runnable() {
+      @Override
+      public void run() {}
+    };
+  }
+}