Change the toolbar to use two stack views

Having two stack views allow the animation to be focused on the location
bar instead of having side effects on the buttons on the side.
It also makes sure the toolbar is respecting the Safe Area on iPhone X
landscape.

Bug: 791933, 791944
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Ib6f0b3560c825cdfe67f5aca648ee0a2b96044a0
Reviewed-on: https://chromium-review.googlesource.com/807930
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Reviewed-by: Stepan Khapugin <stkhapugin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521742}

ios/chrome/browser/ui/toolbar/clean/toolbar_view_controller.mm

@@ -32,8 +32,16 @@
 @interface ToolbarViewController ()
 @property(nonatomic, strong) ToolbarButtonFactory* buttonFactory;
 @property(nonatomic, strong) ToolbarButtonUpdater* buttonUpdater;
+
+// The main objects in the view. Positionned as
+// [leadingStackView][locationBarContainer][trailingStackView]. The stack views
+// contain the buttons which should be shown on each sides of the location bar.
+@property(nonatomic, strong) UIStackView* leadingStackView;
 @property(nonatomic, strong) UIView* locationBarContainer;
-@property(nonatomic, strong) UIStackView* stackView;
+@property(nonatomic, strong) UIStackView* trailingStackView;
+
+// Array containing all the toolbar buttons, lazily instantiated.
+@property(nonatomic, strong) NSArray<ToolbarButton*>* allButtons;
 @property(nonatomic, strong) ToolbarButton* backButton;
 @property(nonatomic, strong) ToolbarButton* forwardButton;
 @property(nonatomic, strong) ToolbarButton* tabSwitchStripButton;
@@ -68,13 +76,15 @@
 @end
 
 @implementation ToolbarViewController
+@synthesize allButtons = _allButtons;
 @synthesize backgroundView = _backgroundView;
 @synthesize buttonFactory = _buttonFactory;
 @synthesize buttonUpdater = _buttonUpdater;
 @synthesize dispatcher = _dispatcher;
 @synthesize expanded = _expanded;
 @synthesize locationBarView = _locationBarView;
-@synthesize stackView = _stackView;
+@synthesize leadingStackView = _leadingStackView;
+@synthesize trailingStackView = _trailingStackView;
 @synthesize loading = _loading;
 @synthesize locationBarContainer = _locationBarContainer;
 @synthesize backButton = _backButton;
@@ -180,7 +190,9 @@
 
   [self setUpToolbarStackView];
   [self setUpLocationBarContainerView];
-  [self.view addSubview:self.stackView];
+  [self.view addSubview:self.leadingStackView];
+  [self.view addSubview:self.locationBarContainer];
+  [self.view addSubview:self.trailingStackView];
   [self.view addSubview:self.shadowView];
   [self.view addSubview:self.progressBar];
   [self setConstraints];
@@ -195,14 +207,19 @@
 
 // Sets up the StackView that contains toolbar navigation items.
 - (void)setUpToolbarStackView {
-  self.stackView = [[UIStackView alloc] initWithArrangedSubviews:@[
-    self.backButton, self.forwardButton, self.reloadButton, self.stopButton,
-    self.locationBarContainer, self.shareButton, self.tabSwitchStripButton,
-    self.toolsMenuButton
+  self.leadingStackView = [[UIStackView alloc] initWithArrangedSubviews:@[
+    self.backButton, self.forwardButton, self.reloadButton, self.stopButton
   ]];
-  self.stackView.translatesAutoresizingMaskIntoConstraints = NO;
-  self.stackView.spacing = kStackViewSpacing;
-  self.stackView.distribution = UIStackViewDistributionFill;
+  self.leadingStackView.translatesAutoresizingMaskIntoConstraints = NO;
+  self.leadingStackView.spacing = kStackViewSpacing;
+  self.leadingStackView.distribution = UIStackViewDistributionFill;
+
+  self.trailingStackView = [[UIStackView alloc] initWithArrangedSubviews:@[
+    self.shareButton, self.tabSwitchStripButton, self.toolsMenuButton
+  ]];
+  self.trailingStackView.translatesAutoresizingMaskIntoConstraints = NO;
+  self.trailingStackView.spacing = kStackViewSpacing;
+  self.trailingStackView.distribution = UIStackViewDistributionFill;
 }
 
 // Sets up the LocationContainerView. Which contains a StackView containing the
@@ -235,7 +252,7 @@
       .active = YES;
 
   // ProgressBar constraints.
-  NSArray* progressBarConstraints = @[
+  [NSLayoutConstraint activateConstraints:@[
     [self.progressBar.leadingAnchor
         constraintEqualToAnchor:self.view.leadingAnchor],
     [self.progressBar.trailingAnchor
@@ -244,8 +261,7 @@
         constraintEqualToAnchor:self.view.bottomAnchor],
     [self.progressBar.heightAnchor
         constraintEqualToConstant:kProgressBarHeight],
-  ];
-  [NSLayoutConstraint activateConstraints:progressBarConstraints];
+  ]];
 
   // Shadow constraints.
   [NSLayoutConstraint activateConstraints:@[
@@ -258,39 +274,68 @@
         constraintEqualToConstant:kToolbarShadowHeight],
   ]];
 
-  // StackView constraints. The main Toolbar StackView.
-  NSArray* stackViewConstraints = @[
-    [self.stackView.heightAnchor
-        constraintEqualToConstant:kToolbarHeight - 2 * kVerticalMargin],
-    [self.stackView.bottomAnchor constraintEqualToAnchor:self.view.bottomAnchor
-                                                constant:-kVerticalMargin],
-    [self.stackView.leadingAnchor
-        constraintEqualToAnchor:self.view.leadingAnchor
+  // Stack views directly in view constraints. Main StackViews.
+  // Layout: |-[leadingStackView]-[locationBarContainer]-[trailingStackView]-|.
+  UILayoutGuide* viewSafeAreaGuide = SafeAreaLayoutGuideForView(self.view);
+  NSArray* stackViewRegularConstraints = @[
+    [self.leadingStackView.leadingAnchor
+        constraintEqualToAnchor:viewSafeAreaGuide.leadingAnchor
                        constant:kHorizontalMargin],
-    [self.stackView.trailingAnchor
-        constraintEqualToAnchor:self.view.trailingAnchor
-                       constant:-kHorizontalMargin],
+    [self.trailingStackView.trailingAnchor
+        constraintEqualToAnchor:viewSafeAreaGuide.trailingAnchor
+                       constant:-kHorizontalMargin]
+  ];
+  [self.regularToolbarConstraints
+      addObjectsFromArray:stackViewRegularConstraints];
+  [NSLayoutConstraint activateConstraints:stackViewRegularConstraints];
+  ApplyVisualConstraintsWithMetrics(
+      @[
+        @"H:[leadingStack]-(spacing)-[locationBar]-(spacing)-[trailingStack]",
+        @"V:[leadingStack(height)]-(margin)-|",
+        @"V:[trailingStack(height)]-(margin)-|"
+      ],
+      @{
+        @"leadingStack" : self.leadingStackView,
+        @"locationBar" : self.locationBarContainer,
+        @"trailingStack" : self.trailingStackView
+      },
+      @{
+        @"height" : @(kToolbarHeight - 2 * kVerticalMargin),
+        @"margin" : @(kVerticalMargin),
+        @"spacing" : @(kStackViewSpacing)
+      });
+
+  // LocationBarContainer constraints.
+  NSArray* locationBarRegularConstraints = @[
+    [self.locationBarContainer.bottomAnchor
+        constraintEqualToAnchor:self.leadingStackView.bottomAnchor],
+    [self.locationBarContainer.topAnchor
+        constraintEqualToAnchor:self.leadingStackView.topAnchor]
   ];
-  [self.regularToolbarConstraints addObjectsFromArray:stackViewConstraints];
-  [NSLayoutConstraint activateConstraints:stackViewConstraints];
+  [self.regularToolbarConstraints
+      addObjectsFromArray:locationBarRegularConstraints];
+  [NSLayoutConstraint activateConstraints:locationBarRegularConstraints];
 
   // LocationBarStackView constraints. The StackView inside the
   // LocationBarContainer View.
+  UILayoutGuide* locationBarContainerSafeAreaGuide =
+      SafeAreaLayoutGuideForView(self.locationBarContainer);
   NSLayoutConstraint* locationBarContainerStackViewTopConstraint =
       [self.locationBarContainerStackView.topAnchor
           constraintEqualToAnchor:self.locationBarContainer.topAnchor];
-  NSArray* locationBarViewStackViewConstraints = @[
+  [NSLayoutConstraint activateConstraints:@[
     [self.locationBarContainerStackView.bottomAnchor
         constraintEqualToAnchor:self.locationBarContainer.bottomAnchor],
     [self.locationBarContainerStackView.leadingAnchor
-        constraintEqualToAnchor:self.locationBarContainer.leadingAnchor],
+        constraintEqualToAnchor:locationBarContainerSafeAreaGuide
+                                    .leadingAnchor],
     [self.locationBarContainerStackView.trailingAnchor
-        constraintEqualToAnchor:self.locationBarContainer.trailingAnchor],
+        constraintEqualToAnchor:locationBarContainerSafeAreaGuide
+                                    .trailingAnchor],
     locationBarContainerStackViewTopConstraint,
-  ];
+  ]];
   [self.regularToolbarConstraints
       addObject:locationBarContainerStackViewTopConstraint];
-  [NSLayoutConstraint activateConstraints:locationBarViewStackViewConstraints];
 }
 
 #pragma mark - Components Setup
@@ -602,18 +647,24 @@
 
 // Updates all Buttons visibility to match any recent WebState change.
 - (void)updateAllButtonsVisibility {
-  for (UIView* view in self.stackView.arrangedSubviews) {
-    if ([view isKindOfClass:[ToolbarButton class]]) {
-      ToolbarButton* button = base::mac::ObjCCastStrict<ToolbarButton>(view);
-      [button updateHiddenInCurrentSizeClass];
-    }
+  for (ToolbarButton* button in self.allButtons) {
+    [button updateHiddenInCurrentSizeClass];
   }
-  [self.bookmarkButton updateHiddenInCurrentSizeClass];
-  [self.voiceSearchButton updateHiddenInCurrentSizeClass];
 }
 
 #pragma mark - Setters & Getters.
 
+- (NSArray<ToolbarButton*>*)allButtons {
+  if (!_allButtons) {
+    _allButtons = [NSArray
+        arrayWithObjects:self.backButton, self.forwardButton, self.reloadButton,
+                         self.stopButton, self.shareButton,
+                         self.tabSwitchStripButton, self.toolsMenuButton,
+                         self.bookmarkButton, self.voiceSearchButton, nil];
+  }
+  return _allButtons;
+}
+
 - (UIView*)backgroundView {
   if (!_backgroundView) {
     _backgroundView = [[UIView alloc] initWithFrame:CGRectZero];