[Android] Select text when stylus first button is pressed.

content/browser/android/content_view_core_impl.h

 // Copyright 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.
 
 #ifndef CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_
 #define CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_
 
 #include <vector>
 
 #include "base/android/jni_android.h"
@@ skipping 378 matching lines @@
 
   // The owning window that has a hold of main application activity.
   ui::WindowAndroid* window_android_;
 
   // The cache of device's current orientation set from Java side, this value
   // will be sent to Renderer once it is ready.
   int device_orientation_;
 
   bool accessibility_enabled_;
 
+  int mouse_drag_start_x_;
+  int mouse_drag_start_y_;
+
   // Manages injecting Java objects.
   scoped_ptr<JavaBridgeDispatcherHostManager>
       java_bridge_dispatcher_host_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentViewCoreImpl);
 };
 
 bool RegisterContentViewCore(JNIEnv* env);
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_CONTENT_VIEW_CORE_IMPL_H_