Revert "Fix URL clipping on iOS 11."

This reverts commit 2d55caf6.

Reason for revert: fails tests downstream 

Original change's description:
> Fix URL clipping on iOS 11.
> 
> Wraps omnibox textfield into a container that positions the textfield
> inside of itself and clips its bounds so that the optimal clipping is
> used. The clipping logic replicates that of the pre-iOS 11 solution
> with UITextField overrides that are now broken in iOS 11.
> To mask the clipped ends of the omnibox, a ClippingMaskView is used
> as a maskView of the clipping view.
> All of this is behind kClippingTextfield flag that is enabled by
> default.
> 
> Bug: 749788
> Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
> Change-Id: Ia03649618397d19990d39914fe1fb1b152b2760d
> Reviewed-on: https://chromium-review.googlesource.com/779191
> Commit-Queue: Stepan Khapugin <stkhapugin@chromium.org>
> Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
> Reviewed-by: Justin Cohen <justincohen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#525322}

TBR=rohitrao@chromium.org,sdefresne@chromium.org,justincohen@chromium.org,stkhapugin@chromium.org

Change-Id: I6b97cd711ef968ded8ff9a45574d6670b7c7f05f
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 749788
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Reviewed-on: https://chromium-review.googlesource.com/837087Reviewed-by: Stepan Khapugin <stkhapugin@chromium.org>
Commit-Queue: Stepan Khapugin <stkhapugin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#525355}

ios/chrome/browser/BUILD.gn

@@ -128,7 +128,6 @@ source_set("browser") {
     "//ios/chrome/browser/ui/fullscreen",
     "//ios/chrome/browser/ui/history:history_base_feature",
     "//ios/chrome/browser/ui/main:feature_flags",
-    "//ios/chrome/browser/ui/omnibox",
     "//ios/chrome/browser/ui/toolbar:feature",
     "//ios/chrome/browser/ui/toolbar/public:toolbar_base_feature",
     "//ios/chrome/common",

ios/chrome/browser/about_flags.mm

@@ -47,7 +47,6 @@
 #include "ios/chrome/browser/ui/fullscreen/fullscreen_features.h"
 #import "ios/chrome/browser/ui/history/history_base_feature.h"
 #include "ios/chrome/browser/ui/main/main_feature_flags.h"
-#import "ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.h"
 #import "ios/chrome/browser/ui/toolbar/public/toolbar_controller_base_feature.h"
 #import "ios/chrome/browser/ui/toolbar/toolbar_private_base_feature.h"
 #include "ios/chrome/grit/ios_strings.h"
@@ -191,9 +190,6 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
     {"clean-toolbar", flag_descriptions::kCleanToolbarName,
      flag_descriptions::kCleanToolbarDescription, flags_ui::kOsIos,
      FEATURE_VALUE_TYPE(kCleanToolbar)},
-    {"clipping-textfield", flag_descriptions::kClippingTextfieldName,
-     flag_descriptions::kClippingTextfieldDescription, flags_ui::kOsIos,
-     FEATURE_VALUE_TYPE(kClippingTextfield)},
     {"bookmark-new-edit-page", flag_descriptions::kBookmarkNewEditPageName,
      flag_descriptions::kBookmarkNewEditPageDescription, flags_ui::kOsIos,
      FEATURE_VALUE_TYPE(kBookmarkNewEditPage)},

ios/chrome/browser/ios_chrome_flag_descriptions.cc

@@ -35,11 +35,6 @@ const char kCleanToolbarDescription[] =
     "When enabled, the Clean Toolbar will be used instead of "
     "WebToolbarController.";
 
-const char kClippingTextfieldName[] = "Clipping Textfield";
-const char kClippingTextfieldDescription[] =
-    "When enabled, the new URL clipping implementation compatible with iOS 11 "
-    "is used.";
-
 const char kContextualSearch[] = "Contextual Search";
 const char kContextualSearchDescription[] =
     "Whether or not Contextual Search is enabled.";

ios/chrome/browser/ios_chrome_flag_descriptions.h

@@ -29,10 +29,6 @@ extern const char kCaptivePortalDescription[];
 extern const char kCleanToolbarName[];
 extern const char kCleanToolbarDescription[];
 
-// Title and description for the flag to enable Omnibox Clipping.
-extern const char kClippingTextfieldName[];
-extern const char kClippingTextfieldDescription[];
-
 // Title and description for the flag to enable Contextual Search.
 extern const char kContextualSearch[];
 extern const char kContextualSearchDescription[];

ios/chrome/browser/ui/omnibox/BUILD.gn

@@ -7,8 +7,6 @@ source_set("omnibox") {
     "location_bar_controller.cc",
     "location_bar_controller.h",
     "location_bar_delegate.h",
-    "omnibox_clipping_feature.h",
-    "omnibox_clipping_feature.mm",
     "web_omnibox_edit_controller.cc",
     "web_omnibox_edit_controller.h",
   ]
@@ -41,12 +39,6 @@ source_set("omnibox_internal") {
     "autocomplete_suggestion.h",
     "chrome_omnibox_client_ios.h",
     "chrome_omnibox_client_ios.mm",
-    "clipping_mask_view.h",
-    "clipping_mask_view.mm",
-    "clipping_textfield.h",
-    "clipping_textfield.mm",
-    "clipping_textfield_container.h",
-    "clipping_textfield_container.mm",
     "image_retriever.h",
     "location_bar_controller_impl.h",
     "location_bar_controller_impl.mm",
@@ -138,11 +130,9 @@ source_set("unit_tests") {
   configs += [ "//build/config/compiler:enable_arc" ]
   testonly = true
   sources = [
-    "clipping_textfield_container_unittest.mm",
     "omnibox_text_field_ios_unittest.mm",
   ]
   deps = [
-    ":omnibox",
     ":omnibox_internal",
     ":resources_unit_tests",
     "//base",

ios/chrome/browser/ui/omnibox/clipping_mask_view.h

-// 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.
-
-#ifndef IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_MASK_VIEW_H_
-#define IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_MASK_VIEW_H_
-
-#import <UIKit/UIKit.h>
-
-// The view used as a mask when the omnibox textfield is being clipped.
-// Displays an opaque rectangle with left, right, or both edges being
-// faded out with transparent gradient.
-@interface ClippingMaskView : UIView
-
-// Whether the left edge is faded.
-@property(nonatomic, assign) BOOL fadeLeft;
-// Whether the right edge is faded.
-@property(nonatomic, assign) BOOL fadeRight;
-
-@end
-
-#endif  // IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_MASK_VIEW_H_

ios/chrome/browser/ui/omnibox/clipping_mask_view.mm

-// 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/omnibox/clipping_mask_view.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-#pragma mark - GradientView
-
-namespace {
-
-enum GradientViewDirection {
-  GRADIENT_LEFT_TO_RIGHT,
-  GRADIENT_RIGHT_TO_LEFT,
-};
-
-}  // namespace
-
-// The gradient view is a view that displays a simple horizontal gradient, from
-// black to transparent.
-@interface GradientView : UIView
-// Sets the gradient's direction. You have to call this at least once to
-// configure the gradient.
-@property(nonatomic, assign) GradientViewDirection direction;
-@end
-
-@implementation GradientView
-@synthesize direction = _direction;
-
-+ (Class)layerClass {
-  return [CAGradientLayer class];
-}
-
-- (void)setDirection:(GradientViewDirection)direction {
-  _direction = direction;
-
-  CAGradientLayer* layer = static_cast<CAGradientLayer*>(self.layer);
-  layer.colors = @[
-    static_cast<id>([[UIColor clearColor] CGColor]),
-    static_cast<id>([[UIColor blackColor] CGColor])
-  ];
-
-  if (direction == GRADIENT_LEFT_TO_RIGHT) {
-    layer.transform = CATransform3DMakeRotation(M_PI_2, 0, 0, 1);
-  } else {
-    layer.transform = CATransform3DMakeRotation(-M_PI_2, 0, 0, 1);
-  }
-
-  [self setNeedsDisplay];
-}
-
-@end
-
-#pragma mark - ClippingMaskView
-
-@interface ClippingMaskView ()
-// The left gradient view.
-@property(nonatomic, strong) GradientView* leftGradientView;
-// The right gradient view.
-@property(nonatomic, strong) GradientView* rightGradientView;
-// The middle view. Used to paint everything not covered by the gradients with
-// opaque color.
-@property(nonatomic, strong) UIView* middleView;
-@end
-
-@implementation ClippingMaskView
-@synthesize fadeLeft = _fadeLeft;
-@synthesize fadeRight = _fadeRight;
-@synthesize middleView = _middleView;
-@synthesize leftGradientView = _leftGradientView;
-@synthesize rightGradientView = _rightGradientView;
-
-- (instancetype)initWithFrame:(CGRect)frame {
-  self = [super initWithFrame:frame];
-  if (self) {
-    _leftGradientView = [[GradientView alloc] init];
-    [_leftGradientView setTranslatesAutoresizingMaskIntoConstraints:NO];
-    _leftGradientView.direction = GRADIENT_RIGHT_TO_LEFT;
-
-    _rightGradientView = [[GradientView alloc] init];
-    [_rightGradientView setTranslatesAutoresizingMaskIntoConstraints:NO];
-    _rightGradientView.direction = GRADIENT_LEFT_TO_RIGHT;
-
-    _middleView = [[UIView alloc] init];
-    [_middleView setTranslatesAutoresizingMaskIntoConstraints:NO];
-    _middleView.backgroundColor = [UIColor blackColor];
-
-    [self addSubview:_leftGradientView];
-    [self addSubview:_middleView];
-    [self addSubview:_rightGradientView];
-  }
-  return self;
-}
-
-- (void)setFadeLeft:(BOOL)fadeLeft {
-  _fadeLeft = fadeLeft;
-  self.leftGradientView.hidden = !fadeLeft;
-}
-
-- (void)setFadeRight:(BOOL)fadeRight {
-  _fadeRight = fadeRight;
-  self.rightGradientView.hidden = !fadeRight;
-}
-
-// Since this view is intended to be used as a maskView of another UIView, and
-// maskViews are not in the view hierarchy, autolayout is not supported.
-// Luckily, the desired layout is easy:
-// |[leftGradientView][middleView][rightGradientView]|,
-// where the grad views are sometimes hidden (and then the middle view is
-// extended to that side). The gradients' widths are equal to the height of this
-// view.
-- (void)layoutSubviews {
-  [super layoutSubviews];
-  CGFloat height = self.bounds.size.height;
-  CGFloat gradientWidth = height;
-  CGFloat xOffset = 0;
-  if (self.fadeLeft) {
-    self.leftGradientView.frame = CGRectMake(0, 0, gradientWidth, height);
-    xOffset += gradientWidth;
-  }
-
-  CGFloat midWidth = self.bounds.size.width - xOffset;
-  if (self.fadeRight) {
-    midWidth -= gradientWidth;
-  }
-
-  self.middleView.frame = CGRectMake(xOffset, 0, midWidth, height);
-  xOffset += midWidth;
-
-  if (self.fadeRight) {
-    self.rightGradientView.frame =
-        CGRectMake(xOffset, 0, gradientWidth, height);
-  }
-}
-
-@end

ios/chrome/browser/ui/omnibox/clipping_textfield.h

-// 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.
-
-#ifndef IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_H_
-#define IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_H_
-
-#import <UIKit/UIKit.h>
-
-@protocol ClippingTextFieldDelegate;
-
-// This textfield subclass is designed to be paired with
-// ClippingTextFieldContainer. It notifies its delegate about changes of text
-// and becoming/resigning first responder.
-@interface ClippingTextField : UITextField
-
-@property(nonatomic, weak) id<ClippingTextFieldDelegate>
-    clippingTextfieldDelegate;
-
-@end
-
-@protocol ClippingTextFieldDelegate
-
-// Called when setText: or setAttributedText: was called. Not called when the
-// textfield is being typed into.
-- (void)textFieldTextChanged:(UITextField*)sender;
-- (void)textFieldBecameFirstResponder:(UITextField*)sender;
-- (void)textFieldResignedFirstResponder:(UITextField*)sender;
-
-@end
-
-#endif  // IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_H_

ios/chrome/browser/ui/omnibox/clipping_textfield.mm

-// 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/omnibox/clipping_textfield.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-@implementation ClippingTextField
-@synthesize clippingTextfieldDelegate = _clippingTextfieldDelegate;
-
-- (void)setText:(NSString*)setText {
-  [super setText:setText];
-  [self.clippingTextfieldDelegate textFieldTextChanged:self];
-}
-
-- (void)setAttributedText:(NSAttributedString*)attributedText {
-  [super setAttributedText:attributedText];
-  [self.clippingTextfieldDelegate textFieldTextChanged:self];
-}
-
-- (BOOL)becomeFirstResponder {
-  BOOL didBecomeFirstResponder = [super becomeFirstResponder];
-  [self.clippingTextfieldDelegate textFieldBecameFirstResponder:self];
-  return didBecomeFirstResponder;
-}
-
-- (BOOL)resignFirstResponder {
-  BOOL didResignFirstResponder = [super resignFirstResponder];
-  if (didResignFirstResponder) {
-    [self.clippingTextfieldDelegate textFieldResignedFirstResponder:self];
-  }
-  return didResignFirstResponder;
-}
-
-@end

ios/chrome/browser/ui/omnibox/clipping_textfield_container.h

-// 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.
-
-#ifndef IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_CONTAINER_H_
-#define IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_CONTAINER_H_
-
-#import "ios/chrome/browser/ui/omnibox/clipping_textfield.h"
-
-// A container for the textfield that manages clipping it appropriately.
-// It will size the textfield to fit precisely when the textfield is first
-// responder. Otherwise, it will clip the textfield to its own bounds in the
-// best way to fit the most significant part of the URL, like this:
-//
-//                     --------------------
-// www.somereallyreally|longdomainname.com|/path/gets/clipped
-//                     --------------------
-// {  clipped prefix  } {  visible text  } { clipped suffix }
-//
-// The clipped parts will also be masked with a gradient fade effect on the
-// clipped ends.
-@interface ClippingTextFieldContainer : UIView<ClippingTextFieldDelegate>
-
-// The only available initializer. This will immediately add |textField| as its
-// subview and set |self| as textField's clipping delegate.
-- (instancetype)initWithClippingTextField:(ClippingTextField*)textField
-    NS_DESIGNATED_INITIALIZER;
-
-- (instancetype)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
-- (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
-
-// Managed textfield.
-@property(nonatomic, strong, readonly) ClippingTextField* textField;
-
-@end
-
-#endif  // IOS_CHROME_BROWSER_UI_OMNIBOX_CLIPPING_TEXTFIELD_CONTAINER_H_

ios/chrome/browser/ui/omnibox/clipping_textfield_container.mm

-// 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/omnibox/clipping_textfield_container.h"
-
-#include "base/strings/sys_string_conversions.h"
-#include "components/omnibox/browser/autocomplete_input.h"
-#include "ios/chrome/browser/autocomplete/autocomplete_scheme_classifier_impl.h"
-#import "ios/chrome/browser/ui/omnibox/clipping_mask_view.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-@interface ClippingTextFieldContainer ()
-
-@property(nonatomic, strong) NSLayoutConstraint* leftConstraint;
-@property(nonatomic, strong) NSLayoutConstraint* rightConstraint;
-@property(nonatomic, strong) ClippingMaskView* gradientMaskView;
-@property(nonatomic, assign, getter=isClipping) BOOL clipping;
-
-@end
-
-@implementation ClippingTextFieldContainer
-@synthesize textField = _textField;
-@synthesize leftConstraint = _leftConstraint;
-@synthesize rightConstraint = _rightConstraint;
-@synthesize gradientMaskView = _gradientMaskView;
-@synthesize clipping = _clipping;
-
-- (instancetype)initWithClippingTextField:(ClippingTextField*)textField {
-  self = [super initWithFrame:CGRectZero];
-  if (self) {
-    _textField = textField;
-    textField.clippingTextfieldDelegate = self;
-    [self addSubview:textField];
-
-    _gradientMaskView = [[ClippingMaskView alloc] init];
-    self.maskView = _gradientMaskView;
-
-    // Configure layout.
-    // Left and Right are used instead of Leading and Trailing because the
-    // clipping only ever applies to URLs that are always displayed in LTR.
-    _leftConstraint =
-        [self.textField.leftAnchor constraintEqualToAnchor:self.leftAnchor];
-    _rightConstraint =
-        [self.textField.rightAnchor constraintEqualToAnchor:self.rightAnchor];
-    [NSLayoutConstraint activateConstraints:@[
-      [textField.topAnchor constraintEqualToAnchor:self.topAnchor],
-      [textField.bottomAnchor constraintEqualToAnchor:self.bottomAnchor],
-      _leftConstraint,
-      _rightConstraint,
-    ]];
-    textField.translatesAutoresizingMaskIntoConstraints = NO;
-    self.clipsToBounds = YES;
-    _clipping = NO;
-  }
-  return self;
-}
-
-- (void)layoutSubviews {
-  if ([self isClipping]) {
-    [self applyClipping];
-  }
-  [super layoutSubviews];
-  self.gradientMaskView.frame = self.bounds;
-}
-
-- (void)startClipping {
-  self.clipping = YES;
-  [self applyClipping];
-  [self setNeedsLayout];
-  [self layoutIfNeeded];
-}
-
-- (void)applyClipping {
-  CGFloat suffixWidth = 0;
-  CGFloat prefixWidth =
-      -[self leftConstantWithAttributedText:self.textField.attributedText
-                              rightConstant:&suffixWidth];
-
-  [self applyGradientsToPrefix:(prefixWidth < 0) suffix:(suffixWidth > 0)];
-
-  self.leftConstraint.constant = prefixWidth;
-  self.rightConstraint.constant = suffixWidth;
-}
-
-- (void)stopClipping {
-  if (![self isClipping]) {
-    return;
-  }
-  self.clipping = NO;
-  self.leftConstraint.constant = 0;
-  self.rightConstraint.constant = 0;
-  [self removeGradient];
-}
-
-// Fade the beginning and/or end of the visible string to indicate to the user
-// that the URL has been clipped.
-- (void)applyGradientsToPrefix:(BOOL)shouldApplyToPrefix
-                        suffix:(BOOL)shouldApplyToSuffix {
-  self.gradientMaskView.fadeLeft = shouldApplyToPrefix;
-  self.gradientMaskView.fadeRight = shouldApplyToSuffix;
-}
-
-- (void)removeGradient {
-  [self applyGradientsToPrefix:NO suffix:NO];
-}
-
-#pragma mark calculate clipping
-
-// Calculates the length (in pts) of the clipped text on the left and
-// right sides of the omnibox in order to show the most significant part of
-// the hostname.
-- (CGFloat)leftConstantWithAttributedText:(NSAttributedString*)attributedText
-                            rightConstant:(out CGFloat*)right {
-  // The goal is to always show the most significant part of the hostname
-  // (i.e. the end of the TLD).
-  //
-  //                     --------------------
-  // www.somereallyreally|longdomainname.com|/path/gets/clipped
-  //                     --------------------
-  // {  clipped prefix  } {  visible text  } { clipped suffix }
-
-  // First find how much (if any) of the scheme/host needs to be clipped so that
-  // the end of the TLD fits in bounds.
-
-  CGFloat widthOfClippedPrefix = 0;
-  url::Component scheme, host;
-  AutocompleteInput::ParseForEmphasizeComponents(
-      base::SysNSStringToUTF16(attributedText.string),
-      AutocompleteSchemeClassifierImpl(), &scheme, &host);
-  if (host.len < 0) {
-    return 0;
-  }
-  NSRange hostRange = NSMakeRange(0, host.begin + host.len);
-  NSAttributedString* hostString =
-      [attributedText attributedSubstringFromRange:hostRange];
-  CGFloat widthOfHost = ceil(hostString.size.width);
-  widthOfClippedPrefix = MAX(widthOfHost - self.bounds.size.width, 0);
-
-  // Now determine if there is any text that will need to be truncated because
-  // there's not enough room.
-  int textWidth = ceil(attributedText.size.width);
-  CGFloat widthOfClippedSuffix =
-      MAX(textWidth - self.bounds.size.width - widthOfClippedPrefix, 0);
-  *right = widthOfClippedSuffix;
-  return widthOfClippedPrefix;
-}
-
-#pragma mark - ClippingTextFieldDelegate
-
-- (void)textFieldTextChanged:(UITextField*)sender {
-  [self startClipping];
-}
-
-- (void)textFieldBecameFirstResponder:(UITextField*)sender {
-  [self stopClipping];
-}
-
-- (void)textFieldResignedFirstResponder:(UITextField*)sender {
-  [self startClipping];
-}
-
-@end

ios/chrome/browser/ui/omnibox/clipping_textfield_container_unittest.mm

-// 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/omnibox/clipping_textfield_container.h"
-
-#include "testing/platform_test.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-namespace {
-
-class ClippingTextFieldContainerTest : public PlatformTest {
- protected:
-  void SetUp() override {
-    PlatformTest::SetUp();
-    textField_ = [[ClippingTextField alloc] init];
-    container_ = [[ClippingTextFieldContainer alloc]
-        initWithClippingTextField:textField_];
-
-    [[[UIApplication sharedApplication] keyWindow] addSubview:container_];
-    // Width of 200 is enough to fit "http://www.google.com" and is
-    // in the same ballpark as iPhone omnibox.
-    container_.frame = CGRectMake(0, 0, 200, 20);
-  };
-
-  void TearDown() override { [container_ removeFromSuperview]; }
-
-  ClippingTextFieldContainer* container_;
-  ClippingTextField* textField_;
-
-  UIView* LeftDecorationView() {
-    // The decoration container contains the decoration views covering the
-    // tail and the head.
-    UIView* decorationContainer = container_.maskView;
-    CGPoint leftMidPoint = CGPointMake(0, container_.bounds.size.height / 2);
-    for (UIView* decorationView in decorationContainer.subviews) {
-      if (CGRectContainsPoint(decorationView.frame, leftMidPoint)) {
-        return decorationView;
-      }
-    }
-    return nil;
-  }
-
-  UIView* RightDecorationView() {
-    // The decoration container contains the decoration views covering the
-    // tail and the head.
-    UIView* decorationContainer = container_.maskView;
-    // Substract 0.5pt from x coordinate because CGRectContainsPoint
-    // returns NO for points on the maximum X edge.
-    CGPoint rightMidPoint = CGPointMake(container_.bounds.size.width - 0.5,
-                                        container_.bounds.size.height / 2);
-    for (UIView* decorationView in decorationContainer.subviews) {
-      if (CGRectContainsPoint(decorationView.frame, rightMidPoint)) {
-        return decorationView;
-      }
-    }
-    return nil;
-  }
-};
-
-TEST_F(ClippingTextFieldContainerTest, DoesntClipWhenEntireURLFits) {
-  NSString* text = @"http://www.google.com";
-  [textField_ setText:text];
-
-  // The textfield fits in the container.
-  EXPECT_LE(textField_.frame.size.width, container_.frame.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, ClipsLongPrefix) {
-  NSString* text = @"http://verylongprefixwaymorethan200pts.google.com";
-  [textField_ setText:text];
-
-  // The left edge is clipped, so the textfield is shifted left.
-  EXPECT_TRUE(textField_.frame.origin.x < 0);
-  // The amount it's shifted left by is just enough to fit the URL.
-  EXPECT_EQ(textField_.frame.origin.x + textField_.frame.size.width,
-            container_.frame.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, ClipsLongSuffix) {
-  NSString* text = @"http://www.google.com/verylongsuffixwaymorethan200pts";
-  [textField_ setText:text];
-
-  // The left edge is not clipped.
-  EXPECT_EQ(textField_.frame.origin.x, 0);
-  // The right edge is clipped.
-  EXPECT_GE(textField_.frame.size.width, container_.frame.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, ClipsPrefixAndSuffix) {
-  NSString* text =
-      @"http://verylongprefixwaymorethan200pts.google.com/"
-      @"verylongsuffixwaymorethan200pts";
-  [textField_ setText:text];
-  CGSize textSize = [[textField_ attributedText] size];
-
-  // The left edge is clipped.
-  EXPECT_TRUE(textField_.frame.origin.x < 0);
-  // The right edge is clipped.
-  EXPECT_GE(textField_.frame.size.width + textField_.frame.origin.x,
-            container_.frame.size.width);
-  // The textfield expands to fit the text.
-  EXPECT_EQ(textField_.frame.size.width, ceil(textSize.width));
-}
-
-TEST_F(ClippingTextFieldContainerTest, NoScheme) {
-  NSString* text = @"www.google.com";
-  [textField_ setText:text];
-
-  // The textfield fits in the container.
-  EXPECT_LE(textField_.frame.size.width, container_.frame.size.width);
-  // The left edge is not clipped.
-  EXPECT_EQ(textField_.frame.origin.x, 0);
-
-  // Textfield's size is equal to container size and greater than text.
-  CGSize textSize = [[textField_ attributedText] size];
-  textSize.width = ceil(textSize.width);
-  textSize.height = ceil(textSize.height);
-  EXPECT_EQ(textField_.frame.size.width, container_.bounds.size.width);
-  EXPECT_LE(textSize.width, textField_.bounds.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, NoHost) {
-  NSString* text = @"http://";
-  [textField_ setText:text];
-
-  // The textfield fits in the container.
-  EXPECT_LE(textField_.frame.size.width, container_.frame.size.width);
-  // The left edge is not clipped.
-  EXPECT_EQ(textField_.frame.origin.x, 0);
-
-  // Textfield's size is equal to container size and greater than text.
-  CGSize textSize = [[textField_ attributedText] size];
-  textSize.width = ceil(textSize.width);
-  textSize.height = ceil(textSize.height);
-  EXPECT_EQ(textField_.frame.size.width, container_.bounds.size.width);
-  EXPECT_LE(textSize.width, textField_.bounds.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, DoesntClipWhenFocused) {
-  NSString* text =
-      @"http://verylongprefixwaymorethan200pts.google.com/"
-      @"verylongsuffixwaymorethan200pts";
-  [textField_ setText:text];
-
-  // The left edge is clipped.
-  EXPECT_TRUE(textField_.frame.origin.x < 0);
-  // The right edge is clipped.
-  EXPECT_GE(textField_.frame.size.width + textField_.frame.origin.x,
-            container_.frame.size.width);
-
-  [textField_ becomeFirstResponder];
-  [container_ layoutIfNeeded];
-
-  // When focused, the textfield should take the container's space and
-  // not be clipped.
-  EXPECT_EQ(textField_.frame.origin.x, 0);
-  EXPECT_EQ(textField_.frame.size.width, container_.frame.size.width);
-
-  [textField_ resignFirstResponder];
-  [container_ layoutIfNeeded];
-
-  // The left edge is clipped.
-  EXPECT_TRUE(textField_.frame.origin.x < 0);
-  // The right edge is clipped.
-  EXPECT_GE(textField_.frame.size.width + textField_.frame.origin.x,
-            container_.frame.size.width);
-}
-
-TEST_F(ClippingTextFieldContainerTest, ShowsDecorationsWhenClipping) {
-  NSString* text =
-      @"http://verylongprefixwaymorethan200pts.google.com/"
-      @"verylongsuffixwaymorethan200pts";
-  [textField_ setText:text];
-
-  // Tail and head are masked when the ends are clipped.
-  EXPECT_FALSE(LeftDecorationView().hidden);
-  EXPECT_FALSE(RightDecorationView().hidden);
-
-  [textField_ becomeFirstResponder];
-  [container_ layoutIfNeeded];
-
-  // Even for long strings, the masks are disabled while editing.
-  EXPECT_TRUE(LeftDecorationView().hidden);
-  EXPECT_TRUE(RightDecorationView().hidden);
-
-  [textField_ resignFirstResponder];
-  [container_ layoutIfNeeded];
-
-  // Deselecting textfield with a long string remasks the ends.
-  EXPECT_FALSE(LeftDecorationView().hidden);
-  EXPECT_FALSE(RightDecorationView().hidden);
-}
-
-}  // namespace

ios/chrome/browser/ui/omnibox/location_bar_view.mm

@@ -5,8 +5,6 @@
 #import "ios/chrome/browser/ui/omnibox/location_bar_view.h"
 
 #import "ios/chrome/browser/ui/animation_util.h"
-#import "ios/chrome/browser/ui/omnibox/clipping_textfield_container.h"
-#import "ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.h"
 #import "ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h"
 #import "ios/chrome/browser/ui/toolbar/public/web_toolbar_controller_constants.h"
 #include "ios/chrome/browser/ui/ui_util.h"
@@ -62,10 +60,6 @@ const CGFloat kTextFieldLeadingOffsetImage = 6;
 // When the |leadingButton| is not hidden, this is a constraint that links the
 // leading edge of the button to self leading edge. Used for animations.
 @property(nonatomic, strong) NSLayoutConstraint* leadingButtonLeadingConstraint;
-// The textfield container. The |textField| is contained in it, and its frame
-// should not be managed directly, instead the location bar uses this container.
-// This is required to achieve desired text clipping of long URLs.
-@property(nonatomic, strong) ClippingTextFieldContainer* textFieldContainer;
 @end
 
 @implementation LocationBarView
@@ -74,7 +68,6 @@ const CGFloat kTextFieldLeadingOffsetImage = 6;
 @synthesize leadingTextfieldConstraint = _leadingTextfieldConstraint;
 @synthesize incognito = _incognito;
 @synthesize leadingButtonLeadingConstraint = _leadingButtonLeadingConstraint;
-@synthesize textFieldContainer = _textFieldContainer;
 
 #pragma mark - Public properties
 
@@ -105,55 +98,20 @@ const CGFloat kTextFieldLeadingOffsetImage = 6;
                                                        font:font
                                                   textColor:textColor
                                                   tintColor:tintColor];
+    [self addSubview:_textField];
 
-    if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-      // When clipping is enabled, the text field is put into a container.
-
-      // TODO(crbug.com/789968): remove these insets when the location bar
-      // background is managed by this view and not toolbar controller. These
-      // insets allow the gradient masking of the omnibox to not extend beyond
-      // the omnibox background's visible frame.
-      self.layoutMargins = UIEdgeInsetsMake(3, 3, 3, 3);
-
-      _textFieldContainer = [[ClippingTextFieldContainer alloc]
-          initWithClippingTextField:_textField];
-      [self addSubview:_textFieldContainer];
-
-      _leadingTextfieldConstraint = [_textFieldContainer.leadingAnchor
-          constraintEqualToAnchor:self.leadingAnchor
-                         constant:kTextFieldLeadingOffsetNoImage];
-
-      [NSLayoutConstraint activateConstraints:@[
-        [_textFieldContainer.trailingAnchor
-            constraintEqualToAnchor:self.layoutMarginsGuide.trailingAnchor],
-        [_textFieldContainer.topAnchor
-            constraintEqualToAnchor:self.layoutMarginsGuide.topAnchor],
-        [_textFieldContainer.bottomAnchor
-            constraintEqualToAnchor:self.layoutMarginsGuide.bottomAnchor],
-        _leadingTextfieldConstraint,
-      ]];
-
-      _textFieldContainer.translatesAutoresizingMaskIntoConstraints = NO;
-      [_textFieldContainer
-          setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
-                                          forAxis:
-                                              UILayoutConstraintAxisHorizontal];
-    } else {
-      // Contain the text field directly, with no clipping container.
-      [self addSubview:_textField];
-      _leadingTextfieldConstraint = [_textField.leadingAnchor
-          constraintEqualToAnchor:self.leadingAnchor
-                         constant:kTextFieldLeadingOffsetNoImage];
-
-      [NSLayoutConstraint activateConstraints:@[
-        [_textField.trailingAnchor constraintEqualToAnchor:self.trailingAnchor],
-        [_textField.topAnchor constraintEqualToAnchor:self.topAnchor],
-        [_textField.bottomAnchor constraintEqualToAnchor:self.bottomAnchor],
-        _leadingTextfieldConstraint,
-      ]];
-
-      _textField.translatesAutoresizingMaskIntoConstraints = NO;
-    }
+    _leadingTextfieldConstraint = [_textField.leadingAnchor
+        constraintEqualToAnchor:self.leadingAnchor
+                       constant:kTextFieldLeadingOffsetNoImage];
+
+    [NSLayoutConstraint activateConstraints:@[
+      [_textField.trailingAnchor constraintEqualToAnchor:self.trailingAnchor],
+      [_textField.topAnchor constraintEqualToAnchor:self.topAnchor],
+      [_textField.bottomAnchor constraintEqualToAnchor:self.bottomAnchor],
+      _leadingTextfieldConstraint,
+    ]];
+
+    _textField.translatesAutoresizingMaskIntoConstraints = NO;
   }
   return self;
 }
@@ -169,26 +127,15 @@ const CGFloat kTextFieldLeadingOffsetImage = 6;
   } else {
     [self addSubview:_leadingButton];
     self.leadingTextfieldConstraint.active = NO;
-    self.leadingButtonLeadingConstraint = [self.layoutMarginsGuide.leadingAnchor
+    self.leadingButtonLeadingConstraint = [self.leadingAnchor
         constraintEqualToAnchor:self.leadingButton.leadingAnchor
                        constant:-kLeadingButtonEdgeOffset];
-
-    NSLayoutConstraint* leadingButtonToTextField = nil;
-    if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-      leadingButtonToTextField = [self.leadingButton.trailingAnchor
-          constraintEqualToAnchor:self.textFieldContainer.leadingAnchor
-                         constant:-kTextFieldLeadingOffsetImage];
-    } else {
-      leadingButtonToTextField = [self.leadingButton.trailingAnchor
-          constraintEqualToAnchor:self.textField.leadingAnchor
-                         constant:-kTextFieldLeadingOffsetImage];
-    }
-
     [NSLayoutConstraint activateConstraints:@[
-      [_leadingButton.centerYAnchor
-          constraintEqualToAnchor:self.layoutMarginsGuide.centerYAnchor],
+      [_leadingButton.centerYAnchor constraintEqualToAnchor:self.centerYAnchor],
       self.leadingButtonLeadingConstraint,
-      leadingButtonToTextField,
+      [self.leadingButton.trailingAnchor
+          constraintEqualToAnchor:self.textField.leadingAnchor
+                         constant:-kTextFieldLeadingOffsetImage],
     ]];
   }
 }

ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.h

-// 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.
-
-#ifndef IOS_CHROME_BROWSER_UI_OMNIBOX_OMNIBOX_CLIPPING_FEATURE_H_
-#define IOS_CHROME_BROWSER_UI_OMNIBOX_OMNIBOX_CLIPPING_FEATURE_H_
-
-#include "base/feature_list.h"
-
-// Feature to choose whether to use the iOS 11-compatible textfield clipping.
-extern const base::Feature kClippingTextfield;
-
-#endif  // IOS_CHROME_BROWSER_UI_OMNIBOX_OMNIBOX_CLIPPING_FEATURE_H_

ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.mm

-// 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/omnibox/omnibox_clipping_feature.h"
-
-const base::Feature kClippingTextfield{"kClippingTextfield",
-                                       base::FEATURE_ENABLED_BY_DEFAULT};

ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.h

@@ -5,7 +5,7 @@
 #ifndef IOS_CHROME_BROWSER_UI_OMNIBOX_OMNIBOX_TEXT_FIELD_IOS_H_
 #define IOS_CHROME_BROWSER_UI_OMNIBOX_OMNIBOX_TEXT_FIELD_IOS_H_
 
-#import "ios/chrome/browser/ui/omnibox/clipping_textfield.h"
+#import <UIKit/UIKit.h>
 
 #include "base/strings/string16.h"
 #import "ios/chrome/browser/ui/omnibox/omnibox_text_field_delegate.h"
@@ -17,7 +17,7 @@ typedef enum {
 } OmniboxTextFieldFadeStyle;
 
 // UITextField subclass to allow for adjusting borders.
-@interface OmniboxTextFieldIOS : ClippingTextField
+@interface OmniboxTextFieldIOS : UITextField
 
 // Initialize the omnibox with the given frame, font, text color, and tint
 // color.

ios/chrome/browser/ui/omnibox/omnibox_text_field_ios.mm

@@ -18,7 +18,6 @@
 #include "ios/chrome/browser/autocomplete/autocomplete_scheme_classifier_impl.h"
 #include "ios/chrome/browser/experimental_flags.h"
 #import "ios/chrome/browser/ui/animation_util.h"
-#import "ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.h"
 #include "ios/chrome/browser/ui/omnibox/omnibox_util.h"
 #import "ios/chrome/browser/ui/reversed_animation.h"
 #include "ios/chrome/browser/ui/rtl_geometry.h"
@@ -534,12 +533,6 @@ NSString* const kOmniboxFadeAnimationKey = @"OmniboxFadeAnimation";
 
 // Enumerate url components (host, path) and draw each one in different rect.
 - (void)drawTextInRect:(CGRect)rect {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // With the new clipping logic, this override is unnecessary.
-    [super drawTextInRect:rect];
-    return;
-  }
-
   if (base::ios::IsRunningOnOrLater(11, 1, 0)) {
     // -[UITextField drawTextInRect:] ignores the argument, so we can't do
     // anything on 11.1 and up.
@@ -846,11 +839,6 @@ NSString* const kOmniboxFadeAnimationKey = @"OmniboxFadeAnimation";
 }
 
 - (CGRect)rectForDrawTextInRect:(CGRect)rect {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // With the new clipping logic, this override is unnecessary.
-    return rect;
-  }
-
   // The goal is to always show the most significant part of the hostname
   // (i.e. the end of the TLD).
   //

ios/chrome/browser/ui/omnibox/omnibox_text_field_ios_unittest.mm

@@ -11,7 +11,6 @@
 #include "base/strings/string_split.h"
 #include "base/strings/sys_string_conversions.h"
 #include "ios/chrome/browser/chrome_paths.h"
-#import "ios/chrome/browser/ui/omnibox/omnibox_clipping_feature.h"
 #include "ios/chrome/grit/ios_strings.h"
 #include "testing/gtest_mac.h"
 #include "testing/platform_test.h"
@@ -144,12 +143,6 @@ TEST_F(OmniboxTextFieldTest, enterPreEditState_preEditTextAlignment_change) {
 }
 
 TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_entireURLFits) {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // This test is expected to not work with new text field clipping because
-    // the code to implement clipping will be removed.
-    return;
-  }
-
   NSString* text = @"http://www.google.com";
   [textfield_ setText:text];
   CGSize textSize = [[textfield_ attributedText] size];
@@ -161,12 +154,6 @@ TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_entireURLFits) {
 }
 
 TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_clippedPrefix) {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // This test is expected to not work with new text field clipping because
-    // the code to implement clipping will be removed.
-    return;
-  }
-
   NSString* text = @"http://www.google.com";
   [textfield_ setText:text];
   CGSize textSize = [[textfield_ attributedText] size];
@@ -181,12 +168,6 @@ TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_clippedPrefix) {
 }
 
 TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_clippedSuffix) {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // This test is expected to not work with new text field clipping because
-    // the code to implement clipping will be removed.
-    return;
-  }
-
   NSString* text = @"http://www.google.com/somelongpath";
   [textfield_ setText:text];
   CGSize textSize = [[textfield_ attributedText] size];
@@ -199,12 +180,6 @@ TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_clippedSuffix) {
 }
 
 TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_noScheme) {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // This test is expected to not work with new text field clipping because
-    // the code to implement clipping will be removed.
-    return;
-  }
-
   NSString* text = @"www.google.com";
   [textfield_ setText:text];
   CGSize textSize = [[textfield_ attributedText] size];
@@ -217,12 +192,6 @@ TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_noScheme) {
 // When the text doesn't contain a host the method bails early and returns
 // the |rect| passed in.
 TEST_F(OmniboxTextFieldTest, rectForDrawTextInRect_noHost) {
-  if (base::FeatureList::IsEnabled(kClippingTextfield)) {
-    // This test is expected to not work with new text field clipping because
-    // the code to implement clipping will be removed.
-    return;
-  }
-
   NSString* text = @"http://";
   [textfield_ setText:text];
   CGSize textSize = [[textfield_ attributedText] size];

ios/chrome/browser/ui/toolbar/web_toolbar_controller.mm

@@ -259,9 +259,6 @@ using ios::material::TimingFunction;
   _keyboardDelegate = [[ToolbarAssistiveKeyboardDelegateImpl alloc] init];
   _keyboardDelegate.dispatcher = dispatcher;
   _keyboardDelegate.omniboxTextField = _locationBarView.textField;
-  [_locationBarView
-      setContentCompressionResistancePriority:UILayoutPriorityDefaultLow
-                                      forAxis:UILayoutConstraintAxisHorizontal];
 
   // Disable default drop interactions on the omnibox.
   // TODO(crbug.com/739903): Handle drop events once Chrome iOS is built with