[Android] Use DIP coordinates for GestureFlingStart events

content/browser/android/content_view_core_impl.cc

 // 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.
 
 #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 1164 matching lines @@
   event.data.scrollUpdate.deltaY = -dy / GetDpiScale();
 
   SendGestureEvent(event);
 }
 
 void ContentViewCoreImpl::FlingStart(JNIEnv* env, jobject obj, jlong time_ms,
                                      jfloat x, jfloat y, jfloat vx, jfloat vy) {
   WebGestureEvent event = MakeGestureEvent(
       WebInputEvent::GestureFlingStart, time_ms, x, y);
 
-  // Velocity should not be scaled by DIP since that interacts poorly with the
-  // deceleration constants.  The DIP scaling is done on the renderer.
-  event.data.flingStart.velocityX = vx;
-  event.data.flingStart.velocityY = vy;
+  event.data.flingStart.velocityX = vx / GetDpiScale();
+  event.data.flingStart.velocityY = vy / GetDpiScale();
 
   SendGestureEvent(event);
 }
 
 void ContentViewCoreImpl::FlingCancel(JNIEnv* env, jobject obj, jlong time_ms) {
   WebGestureEvent event = MakeGestureEvent(
       WebInputEvent::GestureFlingCancel, time_ms, 0, 0);
   SendGestureEvent(event);
 }
 
@@ skipping 664 matching lines @@
       reinterpret_cast<ui::ViewAndroid*>(view_android),
       reinterpret_cast<ui::WindowAndroid*>(window_android));
   return reinterpret_cast<intptr_t>(view);
 }
 
 bool RegisterContentViewCore(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace content