[ios] Prepares HistoryVC’s for Search implementation.

- Creates a UISearchController and adds it to the VC.
- Create a HistoryTableUpdater protocol that will be used to communicate
updates from the Container to the TableView.

Screenshots:
https://drive.google.com/open?id=1L6kaO6xZ7WGEoQXjcVGf_RJALtXrG4cM
https://drive.google.com/open?id=1uSec0DEg7ug_5vAu5uRGL6ljsWabuvZt

Bug: 805195
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Icdfa7c6133bb088352bacbf02f59c65df8b4b0d7
Reviewed-on: https://chromium-review.googlesource.com/998813
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550011}

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

@@ -99,6 +99,7 @@ source_set("history_ui") {
     "history_entry_item_interface.h",
     "history_table_container_view_controller.h",
     "history_table_container_view_controller.mm",
+    "history_table_updater_delegate.h",
     "history_table_view_controller.h",
     "history_table_view_controller.mm",
     "history_util.h",

ios/chrome/browser/ui/history/history_table_container_view_controller.h

@@ -7,10 +7,13 @@
 
 #import "ios/chrome/browser/ui/table_view/table_container_view_controller.h"
 
-@class HistoryTableViewController;
+@protocol HistoryTableUpdaterDelegate;
+
 // Container for handling the interaction between its TableViewController, the
 // container BottomToolbar and the SearchController.
 @interface HistoryTableContainerViewController : TableContainerViewController
+- (instancetype)initWithTable:
+    (ChromeTableViewController<HistoryTableUpdaterDelegate>*)table;
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_HISTORY_HISTORY_TABLE_CONTAINER_VIEW_CONTROLLER_H_

ios/chrome/browser/ui/history/history_table_container_view_controller.mm

@@ -6,6 +6,7 @@
 
 #include "base/mac/foundation_util.h"
 #include "components/strings/grit/components_strings.h"
+#include "ios/chrome/browser/ui/history/history_table_view_controller.h"
 #import "ios/chrome/browser/ui/table_view/table_container_bottom_toolbar.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 
@@ -13,9 +14,16 @@
 #error "This file requires ARC support."
 #endif
 
+@interface HistoryTableContainerViewController ()
+// This ViewController's searchController;
+@property(nonatomic, strong) UISearchController* searchController;
+@end
+
 @implementation HistoryTableContainerViewController
+@synthesize searchController = _searchController;
 
-- (instancetype)initWithTable:(ChromeTableViewController*)table {
+- (instancetype)initWithTable:
+    (ChromeTableViewController<HistoryTableUpdaterDelegate>*)table {
   self = [super initWithTable:table];
   if (self) {
     NSString* leadingButtonString = l10n_util::GetNSStringWithFixup(
@@ -31,4 +39,29 @@
   }
   return self;
 }
+
+- (void)viewDidLoad {
+  [super viewDidLoad];
+  [self addSearchController];
+}
+
+// Creates and adds a UISearchController.
+- (void)addSearchController {
+  // Init the searchController with nil so the results are displayed on the same
+  // TableView.
+  self.searchController =
+      [[UISearchController alloc] initWithSearchResultsController:nil];
+  self.searchController.dimsBackgroundDuringPresentation = NO;
+  // For iOS 11 and later, we place the search bar in the navigation bar, if not
+  // we place the search bar in the table view's header.
+  if (@available(iOS 11, *)) {
+    self.navigationItem.searchController = self.searchController;
+    // We want the search bar visible all the time.
+    self.navigationItem.hidesSearchBarWhenScrolling = NO;
+  } else {
+    self.tableViewController.tableView.tableHeaderView =
+        self.searchController.searchBar;
+  }
+}
+
 @end

ios/chrome/browser/ui/history/history_table_updater_delegate.h

+// Copyright 2018 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_HISTORY_HISTORY_TABLE_UPDATER_DELEGATE_H_
+#define IOS_CHROME_BROWSER_UI_HISTORY_HISTORY_TABLE_UPDATER_DELEGATE_H_
+
+// Delegate to communicate updates from History Container to the History
+// TableView
+@protocol HistoryTableUpdaterDelegate
+// Search history for text |query| and display the results. |query| may be nil.
+// If query is empty, show all history items.
+- (void)showHistoryMatchingQuery:(NSString*)query;
+// Deletes selected items from browser history and removes them from the
+// tableView.
+- (void)deleteSelectedItems;
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_HISTORY_HISTORY_TABLE_UPDATER_DELEGATE_H_

ios/chrome/browser/ui/history/history_table_view_controller.h

@@ -9,6 +9,7 @@
 
 #include "base/ios/block_types.h"
 #include "ios/chrome/browser/ui/history/history_consumer.h"
+#include "ios/chrome/browser/ui/history/history_table_updater_delegate.h"
 
 namespace ios {
 class ChromeBrowserState;
@@ -35,7 +36,7 @@ class ChromeBrowserState;
 
 // ChromeTableViewController for displaying history items.
 @interface HistoryTableViewController
-    : ChromeTableViewController<HistoryConsumer>
+    : ChromeTableViewController<HistoryConsumer, HistoryTableUpdaterDelegate>
 // The ViewController's BrowserState.
 @property(nonatomic, assign) ios::ChromeBrowserState* browserState;
 // Abstraction to communicate with HistoryService and WebHistoryService.

ios/chrome/browser/ui/history/history_table_view_controller.mm

@@ -108,12 +108,6 @@ const int kMaxFetchCount = 100;
   return self.tableView.indexPathsForSelectedRows.count;
 }
 
-- (void)showHistoryMatchingQuery:(NSString*)query {
-  self.finishedLoading = NO;
-  self.currentQuery = query;
-  [self fetchHistoryForQuery:query continuation:false];
-}
-
 - (void)deleteSelectedItemsFromHistory {
   // TODO(crbug.com/805190): Migrate.
 }
@@ -397,4 +391,15 @@ const int kMaxFetchCount = 100;
   // TODO(crbug.com/805190): Migrate.
 }
 
+#pragma mark - HistoryTableUpdaterDelegate
+
+- (void)showHistoryMatchingQuery:(NSString*)query {
+  self.finishedLoading = NO;
+  self.currentQuery = query;
+  [self fetchHistoryForQuery:query continuation:false];
+}
+- (void)deleteSelectedItems {
+  // TODO(crbug.com/805190): Migrate.
+}
+
 @end