Export GetLastCommittedEntryIndex and RemoveEntryAtIndex to Java layer

content/browser/frame_host/navigation_controller_android.h

 // Copyright 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 CONTENT_BROWSER_FRAME_HOST_NAVIGATION_CONTROLLER_ANDROID_H_
 #define CONTENT_BROWSER_FRAME_HOST_NAVIGATION_CONTROLLER_ANDROID_H_
 
 #include <jni.h>
 
 #include "base/android/scoped_java_ref.h"
@@ skipping 59 matching lines @@
                                                              jobject /* obj */);
   int GetNavigationHistory(JNIEnv* env, jobject obj, jobject history);
   void GetDirectedNavigationHistory(JNIEnv* env,
                                     jobject obj,
                                     jobject history,
                                     jboolean is_forward,
                                     jint max_entries);
   base::android::ScopedJavaLocalRef<jstring>
       GetOriginalUrlForVisibleNavigationEntry(JNIEnv* env, jobject obj);
   void ClearHistory(JNIEnv* env, jobject obj);
+  int GetLastCommittedEntryIndex(JNIEnv* env, jobject obj);
+  jboolean RemoveEntryAtIndex(JNIEnv* env, jobject obj, jint index);

[Charlie Reis, 2014/10/29 17:06:47]

Just curious, why do you need RemoveEntryAtIndex?  Anything that removes entries
at an arbitrary position is a bit subtle in practice, so I'd like to be sure
there's a good reason for it.  (We've had to restrict the Prune methods using
CanPruneAllButLastCommitted, for example.)

(Also, I think I just spotted a bug in that method: it doesn't update the
pending_entry_index_ after removal.  I'll file and fix that, though.)

[Charlie Reis, 2014/10/29 20:20:55]

For reference, I filed http://crbug.com/428380 for it.  It turns out it's not
buggy but has potentially unexpected behavior: it clears the pending entry. 
That may affect your use case, which is part of why I'm curious about it.

 
  private:
   NavigationController* navigation_controller_;
   base::android::ScopedJavaGlobalRef<jobject> obj_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationControllerAndroid);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_CONTROLLER_ANDROID_H_