[Android WebView] Fix thread unsafety in accessing Java side getters

android_webview/native/aw_settings.h

 // Copyright (c) 2013 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.
 
 #ifndef ANDROID_WEBVIEW_NATIVE_AW_SETTINGS_H_
 #define ANDROID_WEBVIEW_NATIVE_AW_SETTINGS_H_
 
 #include <jni.h>
 
 #include "base/android/jni_helper.h"
@@ skipping 10 matching lines @@
 class AwSettings : public content::WebContentsObserver {
  public:
   static AwSettings* FromWebContents(content::WebContents* web_contents);
 
   AwSettings(JNIEnv* env, jobject obj, jlong web_contents);
   virtual ~AwSettings();
 
   // Called from Java. Methods with "Locked" suffix require that the settings
   // access lock is held during their execution.
   void Destroy(JNIEnv* env, jobject obj);
+  void PopulateWebPreferencesLocked(JNIEnv* env, jobject obj, jlong web_prefs);
   void ResetScrollAndScaleState(JNIEnv* env, jobject obj);
   void UpdateEverythingLocked(JNIEnv* env, jobject obj);
   void UpdateInitialPageScaleLocked(JNIEnv* env, jobject obj);
   void UpdateUserAgentLocked(JNIEnv* env, jobject obj);
   void UpdateWebkitPreferencesLocked(JNIEnv* env, jobject obj);
   void UpdateFormDataPreferencesLocked(JNIEnv* env, jobject obj);
 
   void PopulateWebPreferences(WebPreferences* web_prefs);
 
  private:
@@ skipping 12 matching lines @@
   bool accelerated_2d_canvas_disabled_by_switch_;
 
   JavaObjectWeakGlobalRef aw_settings_;
 };
 
 bool RegisterAwSettings(JNIEnv* env);
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_NATIVE_AW_SETTINGS_H_