Fix incorrect type hint compiler setting (divergent with upstream clojure)

```clojure
  ;;clj - works
  ;;flowstorm - error
  (-> (Component/newBuilder)
    (.setMyView ^MyView$Builder
     (-> (MyView/newBuilder)
         .build))
    .build)
```

```clojure
  ;;clj - error
  ;;flowstorm - error
  (-> (Component/newBuilder)
      (.setMyView ^MyView$Builder
       (.build (MyView/newBuilder)))
      .build))

```

Author: pfeodrippe

src/jvm/clojure/storm/Utils.java

@@ -35,6 +35,8 @@
 import java.util.regex.Pattern;
 
 public class Utils {
+
+    private static final Keyword TAG_KEY = Keyword.intern(null, "tag");
 
 	public static Object mergeMeta(Object x, IPersistentMap m) {
 		if (x instanceof clojure.lang.IObj && RT.count(m) > 0) {
@@ -54,7 +56,9 @@ public static Object mergeMeta(Object x, IPersistentMap m) {
             // m meta overrides the input Object meta when both have
             for (Object meo : m) {
                 IMapEntry me = (IMapEntry) meo;
-                retMeta = retMeta.assoc(me.key(), me.val());
+                if (!TAG_KEY.equals(me.key())) {
+                    retMeta = retMeta.assoc(me.key(), me.val());
+                }
             }
 
             return o.withMeta(retMeta);

test/clojure/test_clojure/storm_typehint_bug.clj

@@ -0,0 +1,26 @@
+(ns clojure.test-clojure.storm-typehint-bug
+  (:require
+   [clojure.test :refer [deftest is testing]])
+  (:import (clojure.testfixtures Component MyView MyView$Builder)))
+
+(def form-1
+  "Returns a function that executes the inline .build call (previously failing)."
+  (fn []
+    (-> (Component/newBuilder)
+        (.setMyView ^MyView$Builder
+         (.build (MyView/newBuilder)))
+        .build)))
+
+(def form-2
+  "Returns a function that executes the threaded -> form (was expected to succeed)."
+  (fn []
+    (-> (Component/newBuilder)
+        (.setMyView ^MyView$Builder
+         (-> (MyView/newBuilder)
+             .build))
+        .build)))
+
+(deftest wrong-type-hint-falls-back-to-reflection-test
+  (testing "Flow-Storm instrumentation matches Clojure's fallback for incorrect hints"
+    (is (thrown? java.lang.ClassCastException (form-1)))
+    (is (some? (form-2)))))

test/java/clojure/testfixtures/Component.java

@@ -0,0 +1,36 @@
+package clojure.testfixtures;
+
+public class Component {
+
+    private final MyView view;
+
+    private Component(MyView view) {
+        this.view = view;
+    }
+
+    public MyView getMyView() {
+        return view;
+    }
+
+    public static Builder newBuilder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+        private MyView view;
+
+        public Builder setMyView(MyView.Builder builder) {
+            this.view = builder == null ? null : builder.build();
+            return this;
+        }
+
+        public Builder setMyView(MyView view) {
+            this.view = view;
+            return this;
+        }
+
+        public Component build() {
+            return new Component(view);
+        }
+    }
+}

test/java/clojure/testfixtures/MyView.java

@@ -0,0 +1,31 @@
+package clojure.testfixtures;
+
+public class MyView {
+
+    private final String id;
+
+    private MyView(String id) {
+        this.id = id;
+    }
+
+    public String id() {
+        return id;
+    }
+
+    public static Builder newBuilder() {
+        return new Builder();
+    }
+
+    public static final class Builder {
+        private String id = "";
+
+        public Builder withId(String id) {
+            this.id = id;
+            return this;
+        }
+
+        public MyView build() {
+            return new MyView(id);
+        }
+    }
+}