[ios] Adds support for Find in Page to the new architecture.

ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm

Index: ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm
diff --git a/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm b/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm
index 18df9692b07d3b428f2c6af9a9591de7e72b816f..32f815f918c89944d2b364f16aed98fd1881dee3 100644
--- a/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm
+++ b/ios/clean/chrome/browser/ui/tab/tab_container_view_controller.mm
@@ -19,7 +19,8 @@ CGFloat kTabStripHeight = 120.0f;
 @interface TabContainerViewController ()
 
 // Container views for child view controllers. The child view controller's
-// view is added as a subview that fills it's container view via autoresizing.
+// view is added as a subview that fills its container view via autoresizing.
+@property(nonatomic, strong) UIView* findBarView;
 @property(nonatomic, strong) UIView* tabStripView;
 @property(nonatomic, strong) UIView* toolbarView;
 @property(nonatomic, strong) UIView* contentView;
@@ -41,6 +42,8 @@ CGFloat kTabStripHeight = 120.0f;
 @implementation TabContainerViewController
 
 @synthesize contentViewController = _contentViewController;
+@synthesize findBarView = _findBarView;
+@synthesize findBarViewController = _findBarViewController;
 @synthesize toolbarViewController = _toolbarViewController;
 @synthesize tabStripViewController = _tabStripViewController;
 @synthesize tabStripView = _tabStripView;
@@ -55,20 +58,27 @@ CGFloat kTabStripHeight = 120.0f;
 
 - (void)viewDidLoad {
   [super viewDidLoad];
+  self.findBarView = [[UIView alloc] init];
   self.tabStripView = [[UIView alloc] init];
   self.toolbarView = [[UIView alloc] init];
   self.contentView = [[UIView alloc] init];
-  [self.view addSubview:self.tabStripView];
-  [self.view addSubview:self.toolbarView];
-  [self.view addSubview:self.contentView];
+  self.findBarView.translatesAutoresizingMaskIntoConstraints = NO;
   self.tabStripView.translatesAutoresizingMaskIntoConstraints = NO;
   self.toolbarView.translatesAutoresizingMaskIntoConstraints = NO;
   self.contentView.translatesAutoresizingMaskIntoConstraints = NO;
   self.view.backgroundColor = [UIColor blackColor];
+  self.findBarView.backgroundColor = [UIColor greenColor];
   self.tabStripView.backgroundColor = [UIColor blackColor];
   self.toolbarView.backgroundColor = [UIColor blackColor];
   self.contentView.backgroundColor = [UIColor blackColor];
 
+  // Views that are added last have the highest z-order.
+  [self.view addSubview:self.tabStripView];
+  [self.view addSubview:self.toolbarView];
+  [self.view addSubview:self.contentView];
+  [self.view addSubview:self.findBarView];
+  self.findBarView.hidden = YES;
+
   [self addChildViewController:self.tabStripViewController
                      toSubview:self.tabStripView];
   [self addChildViewController:self.toolbarViewController
@@ -100,6 +110,18 @@ CGFloat kTabStripHeight = 120.0f;
   _contentViewController = contentViewController;
 }
 
+- (void)setFindBarViewController:(UIViewController*)findBarViewController {
+  if (self.findBarViewController == findBarViewController)
+    return;
+  if ([self isViewLoaded]) {
+    [self detachChildViewController:self.findBarViewController];
+    [self addChildViewController:findBarViewController
+                       toSubview:self.findBarView];
+  }
+  _findBarViewController = findBarViewController;
+  self.findBarView.hidden = (_findBarViewController == nil);
+}
+
 - (void)setToolbarViewController:(UIViewController*)toolbarViewController {
   if (self.toolbarViewController == toolbarViewController)
     return;
@@ -220,7 +242,8 @@ CGFloat kTabStripHeight = 120.0f;
   return nil;
 }
 
-#pragma mark - TabStripActions
+#pragma mark - Action handling
+
 - (void)showTabStrip:(id)sender {
   self.tabStripHeightConstraint.constant = kTabStripHeight;
   // HACK: Remove fake action.
@@ -277,6 +300,15 @@ CGFloat kTabStripHeight = 120.0f;
         constraintEqualToAnchor:self.view.trailingAnchor],
     [self.contentView.bottomAnchor
         constraintEqualToAnchor:self.bottomLayoutGuide.topAnchor],
+
+    [self.findBarView.topAnchor
+        constraintEqualToAnchor:self.toolbarView.topAnchor],
+    [self.findBarView.bottomAnchor
+        constraintEqualToAnchor:self.toolbarView.bottomAnchor],
+    [self.findBarView.leadingAnchor
+        constraintEqualToAnchor:self.toolbarView.leadingAnchor],
+    [self.findBarView.trailingAnchor
+        constraintEqualToAnchor:self.toolbarView.trailingAnchor],
   ];
 }