[ios] Removes Infobar banner drag down gesture.

Removes the ability to swipe down the Infobar banner in order to reveal
the modal. Now only tapping on the Banner should display a Modal.

This is part of the change UX are proposing after the experiment.

Bug: 961343
Change-Id: Ia64198b22ff9c7d32c129f7532ba4491ebb063a2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1804081
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Reviewed-by: Chris Lu <thegreenfrog@chromium.org>
Reviewed-by: Peter Lee <pkl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#696866}

ios/chrome/browser/infobars/infobar_metrics_recorder.h

@@ -35,8 +35,9 @@ enum class MobileMessagesBannerDismissType {
   TimedOut = 0,
   // Infobar Banner was dismissed by being swiped up.
   SwipedUp = 1,
-  // Infobar Banner was dismissed by being dragged into an Infobar Modal.
-  ExpandedToModal = 2,
+  // *DEPRECATED* Infobar Banner was dismissed by being dragged into an Infobar
+  // Modal.
+  ExpandedToModal_DEPRECATED = 2,
   // Infobar Banner was dismissed by being tapped into an Infobar Modal.
   TappedToModal = 3,
   // Highest enumerator. Recommended by Histogram metrics best practices.

ios/chrome/browser/ui/infobars/banners/infobar_banner_view_controller.mm

@@ -51,7 +51,6 @@ const CGFloat kContainerStackVerticalPadding = 18.0;
 const CGFloat kIconWidth = 25.0;
 
 // Gesture constants.
-const CGFloat kChangeInPositionForTransition = 100.0;
 const CGFloat kChangeInPositionForDismissal = -15.0;
 const CGFloat kLongPressTimeDurationInSeconds = 0.4;
 }  // namespace
@@ -313,27 +312,11 @@ const CGFloat kLongPressTimeDurationInSeconds = 0.4;
     self.startingTouch = touchLocation;
     [self animateBannerToScaleUpState];
   } else if (gesture.state == UIGestureRecognizerStateChanged) {
-    self.view.center =
-        CGPointMake(self.view.center.x, self.view.center.y + touchLocation.y -
-                                            self.startingTouch.y);
-    // If dragged down by more than kChangeInPositionForTransition, present
-    // the InfobarModal.
-    BOOL dragDownExceededThreshold =
-        (self.view.center.y - self.originalCenter.y >
-         kChangeInPositionForTransition);
-    if (dragDownExceededThreshold) {
-      base::RecordAction(
-          base::UserMetricsAction("MobileMessagesBannerDraggedDown"));
-      [self.metricsRecorder
-          recordBannerDismissType:MobileMessagesBannerDismissType::
-                                      ExpandedToModal];
-      [self recordBannerOnScreenTime];
-      [self.delegate presentInfobarModalFromBanner];
-      // Since the modal has now been presented prevent any external dismissal.
-      self.shouldDismissAfterTouchesEnded = NO;
-      // Cancel the gesture since the modal has now been presented.
-      gesture.state = UIGestureRecognizerStateCancelled;
-      return;
+    // Don't allow the banner to be dragged down past its original position.
+    CGFloat newYPosition =
+        self.view.center.y + touchLocation.y - self.startingTouch.y;
+    if (newYPosition < self.originalCenter.y) {
+      self.view.center = CGPointMake(self.view.center.x, newYPosition);
     }
   }
 

ios/showcase/infobars/sc_infobar_banner_coordinator_egtest.mm

@@ -89,8 +89,8 @@ using ::showcase_utils::Close;
       assertWithMatcher:grey_nil()];
 }
 
-// Tests that the InfobarModal is presented when the Banner its swiped down.
-- (void)testInfobarBannerSwipeDown {
+// Tests that the InfobarModal is not presented when the Banner its swiped down.
+- (void)testInfobarBannerCantSwipeDown {
   // Check Banner was presented.
   [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
                                           kInfobarBannerViewIdentifier)]
@@ -99,20 +99,17 @@ using ::showcase_utils::Close;
   [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
                                           kInfobarBannerViewIdentifier)]
       performAction:grey_swipeFastInDirection(kGREYDirectionDown)];
-  // Check Modal was presented.
+  // Check the Modal is not presented.
   [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
                                           kInfobarBannerPresentedModalLabel)]
-      assertWithMatcher:grey_notNil()];
-  // Dismiss Modal.
-  [[EarlGrey
-      selectElementWithMatcher:grey_accessibilityID(kInfobarModalCancelButton)]
-      performAction:grey_tap()];
-  // Check neither the Banner nor Modal are presented.
+      assertWithMatcher:grey_nil()];
+  // Check the banner is still interactable by swiping it up.
   [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
                                           kInfobarBannerViewIdentifier)]
-      assertWithMatcher:grey_nil()];
+      performAction:grey_swipeFastInDirection(kGREYDirectionUp)];
+  // Check Banner was dismissed.
   [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
-                                          kInfobarBannerPresentedModalLabel)]
+                                          kInfobarBannerViewIdentifier)]
       assertWithMatcher:grey_nil()];
 }