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

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

Index: ios/clean/chrome/browser/ui/tab/tab_coordinator.mm
diff --git a/ios/clean/chrome/browser/ui/tab/tab_coordinator.mm b/ios/clean/chrome/browser/ui/tab/tab_coordinator.mm
index 59497cb2e159e0165b1fa94e3b025c0ca8759c21..35edf3f2fd6d14701c594755c310c409466afd43 100644
--- a/ios/clean/chrome/browser/ui/tab/tab_coordinator.mm
+++ b/ios/clean/chrome/browser/ui/tab/tab_coordinator.mm
@@ -9,6 +9,7 @@
 #include "base/mac/foundation_util.h"
 #include "base/memory/ptr_util.h"
 #import "ios/clean/chrome/browser/ui/animators/zoom_transition_animator.h"
+#import "ios/clean/chrome/browser/ui/find_in_page/find_in_page_coordinator.h"
 #import "ios/clean/chrome/browser/ui/ntp/new_tab_page_coordinator.h"
 #import "ios/clean/chrome/browser/ui/tab/tab_container_view_controller.h"
 #import "ios/clean/chrome/browser/ui/tab_strip/tab_strip_coordinator.h"
@@ -67,6 +68,12 @@ const BOOL kUseBottomToolbar = NO;
   toolbarCoordinator.context.baseViewController = nil;
   [toolbarCoordinator start];
 
+  // Create the FindInPage coordinator but do not start it.  It will be started
+  // when a find in page operation is invoked.
+  FindInPageCoordinator* findInPageCoordinator =
+      [[FindInPageCoordinator alloc] init];
+  [self addChildCoordinator:findInPageCoordinator];
+
   TabStripCoordinator* tabStripCoordinator = [[TabStripCoordinator alloc] init];
   [self addChildCoordinator:tabStripCoordinator];
   // Unset the base view controller since this is a contained view controller.
@@ -93,7 +100,9 @@ const BOOL kUseBottomToolbar = NO;
 }
 
 - (void)childCoordinatorDidStart:(BrowserCoordinator*)coordinator {
-  if ([coordinator isKindOfClass:[ToolbarCoordinator class]]) {
+  if ([coordinator isKindOfClass:[FindInPageCoordinator class]]) {
+    self.viewController.findBarViewController = coordinator.viewController;
+  } else if ([coordinator isKindOfClass:[ToolbarCoordinator class]]) {
     self.viewController.toolbarViewController = coordinator.viewController;
   } else if ([coordinator isKindOfClass:[WebCoordinator class]]) {
     self.viewController.contentViewController = coordinator.viewController;
@@ -102,6 +111,12 @@ const BOOL kUseBottomToolbar = NO;
   }
 }
 
+- (void)childCoordinatorWillStop:(BrowserCoordinator*)coordinator {
+  if ([coordinator isKindOfClass:[FindInPageCoordinator class]]) {
+    self.viewController.findBarViewController = nil;
+  }
+}
+
 - (BOOL)canAddOverlayCoordinator:(BrowserCoordinator*)overlayCoordinator {
   // This coordinator will always accept overlay coordinators.
   return YES;