Plumb an overscroll callback form the compositor to the Android UI thread.

content/browser/android/content_view_core_impl.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 "content/browser/android/content_view_core_impl.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/android/scoped_java_ref.h"
@@ skipping 371 matching lines @@
 void ContentViewCoreImpl::UpdateScrollOffsetAndPageScaleFactor(int x, int y,
                                                                float scale) {
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
   if (obj.is_null())
     return;
   Java_ContentViewCore_updateScrollOffsetAndPageScaleFactor(env, obj.obj(), x,
                                                             y, scale);
 }
 
+void ContentViewCoreImpl::UpdateUnusedScrollOffset(int x, int y) {
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
+  if (obj.is_null())
+    return;
+  Java_ContentViewCore_updateUnusedScrollOffset(env, obj.obj(), x, y);
+}
+
 void ContentViewCoreImpl::UpdatePageScaleLimits(float minimum_scale,
                                                 float maximum_scale) {
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
   if (obj.is_null())
     return;
   Java_ContentViewCore_updatePageScaleLimits(env, obj.obj(), minimum_scale,
                                              maximum_scale);
 }
 
@@ skipping 980 matching lines @@
   if (!HasField(env, clazz, "mNativeContentViewCore", "I")) {
     DLOG(ERROR) << "Unable to find ContentView.mNativeContentViewCore!";
     return false;
   }
   g_native_content_view = GetFieldID(env, clazz, "mNativeContentViewCore", "I");
 
   return RegisterNativesImpl(env) >= 0;
 }
 
 }  // namespace content