[Workaround] Notify Overscroll Actions that a gesture ended.

ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.mm

Index: ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.mm
diff --git a/ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.mm b/ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.mm
new file mode 100644
index 0000000000000000000000000000000000000000..b9a024b97f8d13db95250d0a817b3155565d9b86
--- /dev/null
+++ b/ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.mm
@@ -0,0 +1,33 @@
+// 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.
+
+#import "ios/chrome/browser/ui/overscroll_actions/overscroll_actions_gesture_recognizer.h"
+
+#import <UIKit/UIGestureRecognizerSubclass.h>
+
+#include "base/mac/scoped_nsobject.h"
+
+@interface OverscrollActionsGestureRecognizer () {
+  base::scoped_nsprotocol<id> target_;

[rohitrao (ping after 24h), 2017/04/12 12:25:57]

This might be better as a weak pointer.

[justincohen, 2017/04/12 16:05:33]

Done.

+  SEL action_;
+}
+@end
+
+@implementation OverscrollActionsGestureRecognizer
+
+- (instancetype)initWithTarget:(id)target action:(SEL)action {
+  self = [super initWithTarget:target action:action];
+  if (self) {
+    target_.reset([target retain]);
+    action_ = action;
+  }
+  return self;
+}
+
+- (void)reset {
+  [super reset];
+  [target_ performSelector:action_ withObject:self];

[rohitrao (ping after 24h), 2017/04/12 12:25:57]

Does the order of these calls matter?  Is it ok to call the action after
resetting the superclass?

[justincohen, 2017/04/12 16:05:33]

It shouldn't matter, as long as the panGesture: call's with the right state
(which is correct at this point)

+}
+
+@end