[ios clean] Add placeholder for NTP bookmarks, chrome home and open tabs.

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

 // Copyright 2016 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/clean/chrome/browser/ui/tab/tab_coordinator.h"
 
 #include <memory>
 
 #include "base/mac/foundation_util.h"
 #include "base/memory/ptr_util.h"
+#include "ios/chrome/browser/chrome_url_constants.h"
 #import "ios/clean/chrome/browser/ui/animators/zoom_transition_animator.h"
-#import "ios/clean/chrome/browser/ui/ntp/new_tab_page_coordinator.h"
+#import "ios/clean/chrome/browser/ui/commands/tab_commands.h"
+#import "ios/clean/chrome/browser/ui/ntp/ntp_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"
 #import "ios/clean/chrome/browser/ui/toolbar/toolbar_coordinator.h"
 #import "ios/clean/chrome/browser/ui/web_contents/web_coordinator.h"
+#import "ios/shared/chrome/browser/ui/browser_list/browser.h"
+#import "ios/shared/chrome/browser/ui/commands/command_dispatcher.h"
 #import "ios/shared/chrome/browser/ui/coordinators/browser_coordinator+internal.h"
 #import "ios/web/public/web_state/web_state.h"
 #import "ios/web/public/web_state/web_state_observer_bridge.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 namespace {
 // Placeholder "experiment" flag. Change this to YES to have the toolbar at the
 // bottom.
 const BOOL kUseBottomToolbar = NO;
 }  // namespace
 
 @interface TabCoordinator ()<CRWWebStateObserver,
+                             TabCommands,
                              UIViewControllerTransitioningDelegate>
 @property(nonatomic, strong) TabContainerViewController* viewController;
+@property(nonatomic, weak) NTPCoordinator* ntpCoordinator;
+@property(nonatomic, weak) WebCoordinator* webCoordinator;
 @end
 
 @implementation TabCoordinator {
   std::unique_ptr<web::WebStateObserverBridge> _webStateObserver;
 }
 
 @synthesize presentationKey = _presentationKey;
 @synthesize viewController = _viewController;
 @synthesize webState = _webState;
+@synthesize webCoordinator = _webCoordinator;
+@synthesize ntpCoordinator = _ntpCoordinator;
 
 #pragma mark - BrowserCoordinator
 
 - (void)start {
   self.viewController = [self newTabContainer];
   self.viewController.transitioningDelegate = self;
   self.viewController.modalPresentationStyle = UIModalPresentationCustom;
   _webStateObserver =
       base::MakeUnique<web::WebStateObserverBridge>(self.webState, self);
 
+  CommandDispatcher* dispatcher = self.browser->dispatcher();
+  // TabCommands
+  [dispatcher startDispatchingToTarget:self forSelector:@selector(loadURL:)];
+
   WebCoordinator* webCoordinator = [[WebCoordinator alloc] init];
   webCoordinator.webState = self.webState;
   [self addChildCoordinator:webCoordinator];
   [webCoordinator start];
+  self.webCoordinator = webCoordinator;
 
   ToolbarCoordinator* toolbarCoordinator = [[ToolbarCoordinator alloc] init];
   toolbarCoordinator.webState = self.webState;
   [self addChildCoordinator:toolbarCoordinator];
   [toolbarCoordinator start];
 
   TabStripCoordinator* tabStripCoordinator = [[TabStripCoordinator alloc] init];
   [self addChildCoordinator:tabStripCoordinator];
   [tabStripCoordinator start];
 
+  // PLACEHOLDER: Fix the order of events here. The ntpCoordinator was already
+  // created above when |webCoordinator.webState = self.webState;| triggers
+  // a load event, but then the webCoordinator stomps on the
+  // contentViewController when it starts afterwards.
+  if (self.webState->GetLastCommittedURL() == GURL(kChromeUINewTabURL)) {
+    self.viewController.contentViewController =
+        self.ntpCoordinator.viewController;
+  }
+
   [super start];
 }
 
 - (void)stop {
   [super stop];
   // PLACEHOLDER: Stop child coordinators here for now. We might deal with this
   // differently later on.
   for (BrowserCoordinator* child in self.children) {
     [child stop];
   }
   _webStateObserver.reset();
+  [self.browser->dispatcher() stopDispatchingToTarget:self];
 }
 
 - (void)childCoordinatorDidStart:(BrowserCoordinator*)childCoordinator {
   if ([childCoordinator isKindOfClass:[ToolbarCoordinator class]]) {
     self.viewController.toolbarViewController = childCoordinator.viewController;
   } else if ([childCoordinator isKindOfClass:[WebCoordinator class]] ||
              [childCoordinator isKindOfClass:[NTPCoordinator class]]) {
     self.viewController.contentViewController = childCoordinator.viewController;
   } else if ([childCoordinator isKindOfClass:[TabStripCoordinator class]]) {
     self.viewController.tabStripViewController =
         childCoordinator.viewController;
   }
 }
 
+- (void)childCoordinatorWillStop:(BrowserCoordinator*)childCoordinator {
+  self.viewController.contentViewController = nil;
+}
+
 - (BOOL)canAddOverlayCoordinator:(BrowserCoordinator*)overlayCoordinator {
   // This coordinator will always accept overlay coordinators.
   return YES;
 }
 
 #pragma mark - Experiment support
 
 // Create and return a new view controller for use as a tab container;
 // experimental configurations determine which subclass of
 // TabContainerViewController to return.
 - (TabContainerViewController*)newTabContainer {
   if (kUseBottomToolbar) {
     return [[BottomToolbarTabViewController alloc] init];
   }
   return [[TopToolbarTabViewController alloc] init];
 }
 
 #pragma mark - CRWWebStateObserver
 
 // This will eventually be called in -didFinishNavigation and perhaps as an
 // optimization in some equivalent to loadURL.
 - (void)webState:(web::WebState*)webState
     didCommitNavigationWithDetails:(const web::LoadCommittedDetails&)details {
-  if (webState->GetLastCommittedURL() == GURL("chrome://newtab/")) {
+  if (webState->GetLastCommittedURL() == GURL(kChromeUINewTabURL)) {
     NTPCoordinator* ntpCoordinator = [[NTPCoordinator alloc] init];
     [self addChildCoordinator:ntpCoordinator];
     [ntpCoordinator start];
+    self.ntpCoordinator = ntpCoordinator;
   }
 }
 
+- (void)webState:(web::WebState*)webState
+    didStartProvisionalNavigationForURL:(const GURL&)URL {
+  if (self.ntpCoordinator) {
+    [self.ntpCoordinator stop];
+    [self removeChildCoordinator:self.ntpCoordinator];
+    self.viewController.contentViewController =
+        self.webCoordinator.viewController;
+  }
+}
+
 #pragma mark - UIViewControllerTransitioningDelegate
 
 - (id<UIViewControllerAnimatedTransitioning>)
 animationControllerForPresentedController:(UIViewController*)presented
                      presentingController:(UIViewController*)presenting
                          sourceController:(UIViewController*)source {
   ZoomTransitionAnimator* animator = [[ZoomTransitionAnimator alloc] init];
   animator.presenting = YES;
   animator.presentationKey = self.presentationKey;
   [animator selectDelegate:@[ source, presenting ]];
   return animator;
 }
 
 - (id<UIViewControllerAnimatedTransitioning>)
 animationControllerForDismissedController:(UIViewController*)dismissed {
   ZoomTransitionAnimator* animator = [[ZoomTransitionAnimator alloc] init];
   animator.presenting = NO;
   animator.presentationKey = self.presentationKey;
   [animator selectDelegate:@[ dismissed.presentingViewController ]];
   return animator;
 }
 
+#pragma mark - TabCommands
+
+- (void)loadURL:(web::NavigationManager::WebLoadParams)params {
+  self.webState->GetNavigationManager()->LoadURLWithParams(params);
+}
+
 @end