Upstream ios/web/web_state/ui support classes

ios/web/web_state/ui/crw_touch_tracking_recognizer.mm

Index: ios/web/web_state/ui/crw_touch_tracking_recognizer.mm
diff --git a/ios/web/web_state/ui/crw_touch_tracking_recognizer.mm b/ios/web/web_state/ui/crw_touch_tracking_recognizer.mm
new file mode 100644
index 0000000000000000000000000000000000000000..48032530eb8e0921325d1a3e3f1db2b91a27aeca
--- /dev/null
+++ b/ios/web/web_state/ui/crw_touch_tracking_recognizer.mm
@@ -0,0 +1,60 @@
+// 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.
+
+#import "ios/web/web_state/ui/crw_touch_tracking_recognizer.h"
+
+@interface CRWTouchTrackingRecognizer () <UIGestureRecognizerDelegate> {
+  __weak id<CRWTouchTrackingDelegate> _delegate;
+}
+@end
+
+@implementation CRWTouchTrackingRecognizer
+
+@synthesize touchTrackingDelegate = _delegate;
+
+- (id)initWithDelegate:(id<CRWTouchTrackingDelegate>)delegate {
+  if ((self = [super init])) {
+    _delegate = delegate;
+    self.delegate = self;
+  }
+  return self;
+}
+
+#pragma mark -
+#pragma mark UIGestureRecognizer Methods
+
+- (void)reset {
+  [super reset];
+}
+
+- (void)touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event {
+  [super touchesBegan:touches withEvent:event];
+  [_delegate touched:YES];
+}
+
+- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event {
+  [super touchesMoved:touches withEvent:event];
+}
+
+- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event {
+  [super touchesEnded:touches withEvent:event];
+  self.state = UIGestureRecognizerStateFailed;
+  [_delegate touched:NO];
+}
+
+- (void)touchesCancelled:(NSSet*)touches withEvent:(UIEvent*)event {
+  [super touchesCancelled:touches withEvent:event];
+  [_delegate touched:NO];
+}
+
+#pragma mark -
+#pragma mark UIGestureRecognizerDelegate Method
+
+- (BOOL)gestureRecognizer:(UIGestureRecognizer*)gestureRecognizer
+    shouldRecognizeSimultaneouslyWithGestureRecognizer:
+        (UIGestureRecognizer*)otherGestureRecognizer {
+  return YES;
+}
+
+@end