Remove entry from map_ of ClipboardMap when jstr is null or empty

ui/base/clipboard/clipboard_android.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/base/clipboard/clipboard_android.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/android/jni_string.h"
@@ skipping 166 matching lines @@
   Java_Clipboard_clear(env, clipboard_manager_);
   map_state_ = MapState::kUpToDate;
   sequence_number_++;
   UpdateLastModifiedTime(base::Time::Now());
 }
 
 void ClipboardMap::SetLastModifiedTimeWithoutRunningCallback(base::Time time) {
   last_modified_time_ = time;
 }
 
-// Add a key:jstr pair to map, but only if jstr is not null, and also
-// not empty.
+// Add a key:jstr pair to map, if jstr is null or is empty, then remove that
+// entry.
 void AddMapEntry(JNIEnv* env,
                  std::map<std::string, std::string>* map,
                  const char* key,
                  const ScopedJavaLocalRef<jstring>& jstr) {
-  if (!jstr.is_null()) {
-    std::string str = ConvertJavaStringToUTF8(env, jstr.obj());
-    if (!str.empty())
-      (*map)[key] = str;
+  if (jstr.is_null()) {
+    map->erase(key);
+    return;
+  }
+  std::string str = ConvertJavaStringToUTF8(env, jstr.obj());
+  if (!str.empty()) {
+    (*map)[key] = str;
+  } else {
+    map->erase(key);
   }
 }
 
 void ClipboardMap::UpdateLastModifiedTime(base::Time time) {
   last_modified_time_ = time;
   // |modified_callback_| may be null in tests.
   if (modified_cb_)
     modified_cb_.Run(time);
 }
 
@@ skipping 342 matching lines @@
   return RegisterNativesImpl(env);
 }
 
 // Returns a pointer to the current ClipboardAndroid object.
 static jlong Init(JNIEnv* env,
                   const base::android::JavaParamRef<jobject>& obj) {
   return reinterpret_cast<intptr_t>(Clipboard::GetForCurrentThread());
 }
 
 } // namespace ui