Forward GenericMotionEvent to EventForwarder

ui/android/java/src/org/chromium/ui/input/JoystickScrollProvider.java

Index: ui/android/java/src/org/chromium/ui/input/JoystickScrollProvider.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/input/JoystickScrollProvider.java b/ui/android/java/src/org/chromium/ui/input/JoystickScrollProvider.java
similarity index 78%
rename from content/public/android/java/src/org/chromium/content/browser/input/JoystickScrollProvider.java
rename to ui/android/java/src/org/chromium/ui/input/JoystickScrollProvider.java
index 8c57b5f8f8531fb34f99ba8a4890ca492b78903d..8f8fbc2288a4501fa4d63566fb22e16b2bdd2307 100644
--- a/content/public/android/java/src/org/chromium/content/browser/input/JoystickScrollProvider.java
+++ b/ui/android/java/src/org/chromium/ui/input/JoystickScrollProvider.java
@@ -1,8 +1,8 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
+// Copyright 2017 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.
 
-package org.chromium.content.browser.input;
+package org.chromium.ui.input;
 
 import android.content.Context;
 import android.util.TypedValue;
@@ -12,9 +12,6 @@ import android.view.View;
 import android.view.animation.AnimationUtils;
 
 import org.chromium.base.Log;
-import org.chromium.base.annotations.CalledByNative;
-import org.chromium.base.annotations.JNINamespace;
-import org.chromium.content_public.browser.WebContents;
 import org.chromium.ui.base.WindowAndroid;
 import org.chromium.ui.display.DisplayAndroid;
 import org.chromium.ui.display.DisplayAndroid.DisplayAndroidObserver;
@@ -22,7 +19,6 @@ import org.chromium.ui.display.DisplayAndroid.DisplayAndroidObserver;
 /**
  * This class implements auto scrolling and panning for gamepad left joystick motion event.
  */
-@JNINamespace("content")
 public class JoystickScrollProvider {
     private static final String TAG = "JoystickScroll";
 
@@ -43,11 +39,26 @@ public class JoystickScrollProvider {
         }
     }
 
-    private WindowAndroid mWindowAndroid;
-    private View mContainerView;
-    private long mNativeJoystickScrollProvider;
-    private JoystickScrollDisplayObserver mDisplayObserver;
+    /**
+     * Actual joystick event should be translated to other input event since Blink does not
+     * support it. This interface is used to provide the way to emulate it.
+     */
+    public interface ScrollEmulator {
+        /**
+         * Called when a scroll event got issued.
+         * @param timeMillis current animation time.
+         * @param dx amount of scroll along x axis.
+         * @param dy amount of scroll along y axis.
+         */
+        void scroll(long timeMillis, float dx, float dy);
+    }
+
+    private final View mContainerView;
+    // Interface used to send an event to Blink to emulate joystick scroll.
+    private final ScrollEmulator mScrollEmulator;
+    private final JoystickScrollDisplayObserver mDisplayObserver;
 
+    private WindowAndroid mWindowAndroid;
     private float mScrollVelocityX;
     private float mScrollVelocityY;
     private float mScrollFactor;
@@ -63,20 +74,14 @@ public class JoystickScrollProvider {
      * Constructs a new JoystickScrollProvider.
      */
     public JoystickScrollProvider(
-            WebContents webContents, View containerView, WindowAndroid windowAndroid) {
-        mNativeJoystickScrollProvider = nativeInit(webContents);
+            View containerView, WindowAndroid windowAndroid, ScrollEmulator scrollEmulator) {
         mContainerView = containerView;
         mWindowAndroid = windowAndroid;
+        mScrollEmulator = scrollEmulator;
         mEnabled = true;
         mDisplayObserver = new JoystickScrollDisplayObserver();
     }
 
-    @CalledByNative
-    private void onNativeObjectDestroyed(long nativePointer) {
-        assert nativePointer == mNativeJoystickScrollProvider;
-        mNativeJoystickScrollProvider = 0;
-    }
-
     /**
      * This function enables or disables scrolling through joystick.
      * @param enabled Decides whether joystick scrolling should be
@@ -118,12 +123,14 @@ public class JoystickScrollProvider {
         Context context = mWindowAndroid == null ? null : mWindowAndroid.getContext().get();
         TypedValue outValue = new TypedValue();
 
-        if (context != null && context.getTheme().resolveAttribute(
-                android.R.attr.listPreferredItemHeight, outValue, true)) {
+        if (context != null
+                && context.getTheme().resolveAttribute(
+                           android.R.attr.listPreferredItemHeight, outValue, true)) {
             mScrollFactor = outValue.getDimension(context.getResources().getDisplayMetrics());
         } else {
             if (context != null) {
-                Log.d(TAG, "Theme attribute listPreferredItemHeight not defined"
+                Log.d(TAG,
+                        "Theme attribute listPreferredItemHeight not defined"
                                 + " switching to fallback scroll factor");
             }
             mScrollFactor = SCROLL_FACTOR_FALLBACK * mDipScale;
@@ -134,6 +141,7 @@ public class JoystickScrollProvider {
      * This function processes motion event and computes new
      * scroll offest in pixels which is propertional to left joystick
      * axes movement.
+     *
      * It also starts runnable to scroll content view core equal to
      * scroll offset pixels.
      *
@@ -143,8 +151,9 @@ public class JoystickScrollProvider {
     public boolean onMotion(MotionEvent event) {
         if (!mEnabled) return false;
         if ((event.getSource() & InputDevice.SOURCE_CLASS_JOYSTICK) == 0) return false;
-        Log.d(TAG, "Joystick left stick axis: " + event.getAxisValue(MotionEvent.AXIS_X) + ","
-                + event.getAxisValue(MotionEvent.AXIS_Y));
+        Log.d(TAG,
+                "Joystick left stick axis: " + event.getAxisValue(MotionEvent.AXIS_X) + ","
+                        + event.getAxisValue(MotionEvent.AXIS_Y));
 
         assert mScrollFactor != 0;
 
@@ -181,10 +190,7 @@ public class JoystickScrollProvider {
         final float dx = (mScrollVelocityX * dt / 1000.f);
         final float dy = (mScrollVelocityY * dt / 1000.f);
 
-        if (mNativeJoystickScrollProvider != 0) {
-            nativeScrollBy(
-                    mNativeJoystickScrollProvider, timeMillis, dx / mDipScale, dy / mDipScale);
-        }
+        if (mScrollEmulator != null) mScrollEmulator.scroll(timeMillis, dx, dy);
 
         mLastAnimateTimeMillis = timeMillis;
         mContainerView.postOnAnimation(mScrollRunnable);
@@ -197,7 +203,7 @@ public class JoystickScrollProvider {
     /**
      * Removes noise from joystick motion events.
      */
-    private float getFilteredAxisValue(MotionEvent event, int axis) {
+    private static float getFilteredAxisValue(MotionEvent event, int axis) {
         float axisValWithNoise = event.getAxisValue(axis);
         if (axisValWithNoise > JOYSTICK_SCROLL_DEADZONE
                 || axisValWithNoise < -JOYSTICK_SCROLL_DEADZONE) {
@@ -205,8 +211,4 @@ public class JoystickScrollProvider {
         }
         return 0f;
     }
-
-    private native long nativeInit(WebContents webContents);
-    private native void nativeScrollBy(
-            long nativeJoystickScrollProvider, long timeMs, float dxDip, float dyDip);
 }