[Android] Perform eager gesture recognition on MotionEvents

content/public/android/java/src/org/chromium/content/browser/ZoomManager.java

Index: content/public/android/java/src/org/chromium/content/browser/ZoomManager.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ZoomManager.java b/content/public/android/java/src/org/chromium/content/browser/ZoomManager.java
deleted file mode 100644
index fd2a5234108dfc2b4de843861fbea19f3d27c89d..0000000000000000000000000000000000000000
--- a/content/public/android/java/src/org/chromium/content/browser/ZoomManager.java
+++ /dev/null
@@ -1,167 +0,0 @@
-// 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.
-
-package org.chromium.content.browser;
-
-import android.annotation.TargetApi;
-import android.content.Context;
-import android.os.Build;
-import android.util.Log;
-import android.view.MotionEvent;
-import android.view.ScaleGestureDetector;
-
-/**
- * ZoomManager is responsible for maintaining the ContentView's current zoom
- * level state and process scaling-related gestures.
- */
-class ZoomManager {
-    private static final String TAG = "ContentViewZoom";
-
-    private final ContentViewCore mContentViewCore;
-
-    // ScaleGestureDetector previous to 4.2.2 failed to record touch event times (b/7626515),
-    // so we record them manually for use when synthesizing pinch gestures.
-    private long mCurrentEventTime;
-
-    private class ScaleGestureListener implements ScaleGestureDetector.OnScaleGestureListener {
-        // Completely silence scaling events. Used in WebView when zoom support
-        // is turned off.
-        private boolean mPermanentlyIgnoreDetectorEvents = false;
-        // Bypass events through the detector to maintain its state. Used when
-        // renderes already handles the touch event.
-        private boolean mTemporarilyIgnoreDetectorEvents = false;
-
-        // Whether any pinch zoom event has been sent to native.
-        private boolean mPinchEventSent;
-
-        long getEventTime(ScaleGestureDetector detector) {
-            // Workaround for b/7626515, fixed in 4.2.2.
-            assert mCurrentEventTime != 0;
-            assert detector.getEventTime() == 0 || detector.getEventTime() == mCurrentEventTime;
-            return mCurrentEventTime;
-        }
-
-        boolean getPermanentlyIgnoreDetectorEvents() {
-            return mPermanentlyIgnoreDetectorEvents;
-        }
-
-        void setPermanentlyIgnoreDetectorEvents(boolean value) {
-            // Note that returning false from onScaleBegin / onScale makes the
-            // gesture detector not to emit further scaling notifications
-            // related to this gesture. Thus, if detector events are enabled in
-            // the middle of the gesture, we don't need to do anything.
-            mPermanentlyIgnoreDetectorEvents = value;
-        }
-
-        void setTemporarilyIgnoreDetectorEvents(boolean value) {
-            mTemporarilyIgnoreDetectorEvents = value;
-        }
-
-        @Override
-        public boolean onScaleBegin(ScaleGestureDetector detector) {
-            if (ignoreDetectorEvents()) return false;
-            mPinchEventSent = false;
-            mContentViewCore.getContentViewGestureHandler().setIgnoreSingleTap(true);
-            return true;
-        }
-
-        @Override
-        public void onScaleEnd(ScaleGestureDetector detector) {
-            if (!mPinchEventSent || !mContentViewCore.isAlive()) return;
-            mContentViewCore.getContentViewGestureHandler().pinchEnd(getEventTime(detector));
-            mPinchEventSent = false;
-        }
-
-        @Override
-        public boolean onScale(ScaleGestureDetector detector) {
-            if (ignoreDetectorEvents()) return false;
-            // It is possible that pinchBegin() was never called when we reach here.
-            // This happens when webkit handles the 2nd touch down event. That causes
-            // ContentView to ignore the onScaleBegin() call. And if webkit does not
-            // handle the touch move events afterwards, we will face a situation
-            // that pinchBy() is called without any pinchBegin().
-            // To solve this problem, we call pinchBegin() here if it is never called.
-            if (!mPinchEventSent) {
-                mContentViewCore.getContentViewGestureHandler().pinchBegin(getEventTime(detector),
-                        (int) detector.getFocusX(), (int) detector.getFocusY());
-                mPinchEventSent = true;
-            }
-            mContentViewCore.getContentViewGestureHandler().pinchBy(
-                    getEventTime(detector), (int) detector.getFocusX(), (int) detector.getFocusY(),
-                    detector.getScaleFactor());
-            return true;
-        }
-
-        private boolean ignoreDetectorEvents() {
-            return mPermanentlyIgnoreDetectorEvents ||
-                    mTemporarilyIgnoreDetectorEvents ||
-                    !mContentViewCore.isAlive();
-        }
-    }
-
-    private final ScaleGestureDetector mMultiTouchDetector;
-    private final ScaleGestureListener mMultiTouchListener;
-
-    ZoomManager(final Context context, ContentViewCore contentViewCore) {
-        mContentViewCore = contentViewCore;
-        mMultiTouchListener = new ScaleGestureListener();
-        mMultiTouchDetector = new ScaleGestureDetector(context, mMultiTouchListener);
-
-        // ScaleGestureDetector's "QuickScale" feature was introduced in KitKat.
-        // As ContentViewGestureHandler already implements this feature,
-        // explicitly disable it to prevent double-handling of the gesture.
-        disableQuickScale(mMultiTouchDetector);
-    }
-
-    boolean isScaleGestureDetectionInProgress() {
-        return !mMultiTouchListener.getPermanentlyIgnoreDetectorEvents()
-                && mMultiTouchDetector.isInProgress();
-    }
-
-    // Passes the touch event to ScaleGestureDetector so that its internal
-    // state won't go wrong, but instructs the listener to ignore the result
-    // of processing, if any.
-    void passTouchEventThrough(MotionEvent event) {
-        mMultiTouchListener.setTemporarilyIgnoreDetectorEvents(true);
-        mCurrentEventTime = event.getEventTime();
-        try {
-            mMultiTouchDetector.onTouchEvent(event);
-        } catch (Exception e) {
-            Log.e(TAG, "ScaleGestureDetector got into a bad state!", e);
-            assert false;
-        }
-    }
-
-    // Passes the touch event to ScaleGestureDetector so that its internal state
-    // won't go wrong. ScaleGestureDetector needs two pointers in a MotionEvent
-    // to recognize a zoom gesture.
-    boolean processTouchEvent(MotionEvent event) {
-        // TODO: Need to deal with multi-touch transition
-        mMultiTouchListener.setTemporarilyIgnoreDetectorEvents(false);
-        mCurrentEventTime = event.getEventTime();
-        try {
-            boolean inGesture = isScaleGestureDetectionInProgress();
-            boolean retVal = mMultiTouchDetector.onTouchEvent(event);
-            if (!inGesture && (event.getActionMasked() == MotionEvent.ACTION_UP
-                    || event.getActionMasked() == MotionEvent.ACTION_CANCEL)) {
-                return false;
-            }
-            return retVal;
-        } catch (Exception e) {
-            Log.e(TAG, "ScaleGestureDetector got into a bad state!", e);
-            assert false;
-        }
-        return false;
-    }
-
-    void updateMultiTouchSupport(boolean supportsMultiTouchZoom) {
-        mMultiTouchListener.setPermanentlyIgnoreDetectorEvents(!supportsMultiTouchZoom);
-    }
-
-    @TargetApi(Build.VERSION_CODES.KITKAT)
-    private static void disableQuickScale(ScaleGestureDetector scaleGestureDetector) {
-       if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) return;
-       scaleGestureDetector.setQuickScaleEnabled(false);
-     }
-}