[Android] Properly handle cancelled scroll events

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

 // 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.
 
 package org.chromium.content.browser;
 
 import android.content.Context;
 import android.util.Log;
 import android.view.MotionEvent;
 import android.view.ScaleGestureDetector;
@@ skipping 105 matching lines @@
 
     // 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);
         try {
             boolean inGesture = isScaleGestureDetectionInProgress();
             boolean retVal = mMultiTouchDetector.onTouchEvent(event);
-            if (event.getActionMasked() == MotionEvent.ACTION_UP && !inGesture) return false;
+            if (!inGesture && (event.getActionMasked() == MotionEvent.ACTION_UP
+                    || event.getActionMasked() == MotionEvent.ACTION_CANCEL)) return false;

[Ted C, 2013/10/14 20:05:38]

braces needed since the conditional no longer fits on one line

[cjhopman, 2013/10/14 20:37:09]

Done.

             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);
     }
 }