Add missing using statements for JNI types.

content/browser/android/web_contents_observer_proxy.cc

 // Copyright 2015 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 "content/browser/android/web_contents_observer_proxy.h"
 
 #include <string>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/android/scoped_java_ref.h"
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/common/android/media_metadata_android.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/navigation_handle.h"
 #include "jni/WebContentsObserverProxy_jni.h"
 
 using base::android::AttachCurrentThread;
+using base::android::JavaParamRef;
 using base::android::ScopedJavaLocalRef;
 using base::android::ConvertUTF8ToJavaString;
 using base::android::ConvertUTF16ToJavaString;
 
 namespace content {
 
 // TODO(dcheng): File a bug. This class incorrectly passes just a frame ID,
 // which is not sufficient to identify a frame (since frame IDs are scoped per
 // render process, and so may collide).
 WebContentsObserverProxy::WebContentsObserverProxy(JNIEnv* env,
@@ skipping 305 matching lines @@
     // a base URL if there has been a loadUrl("javascript:...") after
     // loadDataWithBaseUrl.
     *url = base_url_of_last_started_data_url_.possibly_invalid_spec();
   }
 }
 
 bool RegisterWebContentsObserverProxy(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 }  // namespace content