[iOS] Fix bug where omnibox doesn't defocus on tab switch.

Fixes the bug which was caused by a mistake in a refactoring.
Add a test to prevent regression.

Fixed: 1151035
Change-Id: I9f3d00cfdd13321dd289a9944e155c76bc8b6524
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2600821
Commit-Queue: Robbie Gibson <rkgibson@google.com>
Reviewed-by: Robbie Gibson <rkgibson@google.com>
Auto-Submit: Stepan Khapugin <stkhapugin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840112}

ios/chrome/browser/ui/location_bar/location_bar_coordinator.mm

@@ -201,6 +201,7 @@
   self.mediator.templateURLService =
       ios::TemplateURLServiceFactory::GetForBrowserState(self.browserState);
   self.mediator.consumer = self;
+  self.mediator.webStateList = self.webStateList;
 
   self.steadyViewMediator = [[LocationBarSteadyViewMediator alloc]
       initWithLocationBarModel:[self locationBarModel]];
@@ -235,6 +236,7 @@
   _editController.reset();
 
   self.viewController = nil;
+  [self.mediator disconnect];
   self.mediator = nil;
   [self.steadyViewMediator disconnect];
   self.steadyViewMediator = nil;

ios/chrome/browser/ui/location_bar/location_bar_mediator.h

@@ -9,6 +9,7 @@
 
 @protocol LocationBarConsumer;
 class TemplateURLService;
+class WebStateList;
 
 // A mediator object that updates location bar state not relating to the
 // LocationBarSteadyView. In practice, this is any state not relating to the
@@ -25,6 +26,13 @@ class TemplateURLService;
 // object and may be nil.
 @property(nonatomic, weak) id<LocationBarConsumer> consumer;
 
+// The WebStateList that this mediator listens for any changes on the active web
+// state.
+@property(nonatomic, assign) WebStateList* webStateList;
+
+// Stops observing all objects.
+- (void)disconnect;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_LOCATION_BAR_LOCATION_BAR_MEDIATOR_H_

ios/chrome/browser/ui/location_bar/location_bar_mediator.mm

@@ -11,6 +11,8 @@
 #import "ios/chrome/browser/ui/ntp/ntp_util.h"
 #import "ios/chrome/browser/ui/omnibox/omnibox_util.h"
 #import "ios/chrome/browser/ui/util/uikit_ui_util.h"
+#import "ios/chrome/browser/web_state_list/web_state_list.h"
+#import "ios/chrome/browser/web_state_list/web_state_list_observer_bridge.h"
 #include "ios/chrome/grit/ios_theme_resources.h"
 #include "ios/web/public/navigation/navigation_item.h"
 #import "ios/web/public/navigation/navigation_manager.h"
@@ -20,7 +22,7 @@
 #error "This file requires ARC support."
 #endif
 
-@interface LocationBarMediator () <SearchEngineObserving>
+@interface LocationBarMediator () <SearchEngineObserving, WebStateListObserving>
 
 // Whether the current default search engine supports search by image.
 @property(nonatomic, assign) BOOL searchEngineSupportsSearchByImage;
@@ -29,16 +31,26 @@
 
 @implementation LocationBarMediator {
   std::unique_ptr<SearchEngineObserverBridge> _searchEngineObserver;
+  std::unique_ptr<WebStateListObserverBridge> _webStateListObserver;
 }
 
 - (instancetype)init {
   self = [super init];
   if (self) {
     _searchEngineSupportsSearchByImage = NO;
+    _webStateListObserver = std::make_unique<WebStateListObserverBridge>(self);
   }
   return self;
 }
 
+- (void)disconnect {
+  self.webStateList = nil;
+}
+
+- (void)dealloc {
+  [self disconnect];
+}
+
 #pragma mark - SearchEngineObserving
 
 - (void)searchEngineChanged {
@@ -73,4 +85,27 @@
   }
 }
 
+- (void)setWebStateList:(WebStateList*)webStateList {
+  if (_webStateList) {
+    _webStateList->RemoveObserver(_webStateListObserver.get());
+  }
+
+  _webStateList = webStateList;
+
+  if (_webStateList) {
+    _webStateList->AddObserver(_webStateListObserver.get());
+  }
+}
+
+#pragma mark - WebStateListObserver
+
+- (void)webStateList:(WebStateList*)webStateList
+    didChangeActiveWebState:(web::WebState*)newWebState
+                oldWebState:(web::WebState*)oldWebState
+                    atIndex:(int)atIndex
+                     reason:(ActiveWebStateChangeReason)reason {
+  DCHECK_EQ(_webStateList, webStateList);
+  [self.consumer defocusOmnibox];
+}
+
 @end

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

@@ -238,6 +238,7 @@ source_set("eg2_tests") {
     ":test_support+eg2",
     "//ios/chrome/app/strings:ios_strings_grit",
     "//ios/chrome/browser/ui/content_suggestions:content_suggestions_constant",
+    "//ios/chrome/browser/ui/omnibox/popup:popup_accessibility_identifier_constants",
     "//ios/chrome/test/earl_grey:eg_test_support+eg2",
     "//ios/testing/earl_grey:eg_test_support+eg2",
     "//ios/third_party/earl_grey2:test_lib",

ios/chrome/browser/ui/omnibox/omnibox_egtest.mm

@@ -11,6 +11,7 @@
 #import "base/test/ios/wait_util.h"
 #import "ios/chrome/browser/ui/content_suggestions/ntp_home_constant.h"
 #import "ios/chrome/browser/ui/omnibox/omnibox_app_interface.h"
+#import "ios/chrome/browser/ui/omnibox/popup/omnibox_popup_accessibility_identifier_constants.h"
 #include "ios/chrome/grit/ios_strings.h"
 #import "ios/chrome/test/earl_grey/chrome_earl_grey.h"
 #import "ios/chrome/test/earl_grey/chrome_earl_grey_ui.h"
@@ -421,6 +422,65 @@ id<GREYMatcher> SearchCopiedTextButton() {
       assertWithMatcher:chrome_test_util::OmniboxContainingText(kPage1URL)];
 }
 
+- (void)testOmniboxDefocusesOnTabSwitch {
+  [self openPage1];
+  [ChromeEarlGrey openNewTab];
+  [ChromeEarlGrey waitForMainTabCount:2];
+  [self openPage2];
+
+  [ChromeEarlGreyUI focusOmnibox];
+  [[EarlGrey selectElementWithMatcher:chrome_test_util::Omnibox()]
+      performAction:grey_typeText(@"Obama")];
+
+  // The popup should open.
+  [[EarlGrey
+      selectElementWithMatcher:
+          grey_accessibilityID(kOmniboxPopupTableViewAccessibilityIdentifier)]
+      assertWithMatcher:grey_notNil()];
+
+  // Switch to the first tab.
+  [ChromeEarlGrey selectTabAtIndex:0];
+  [ChromeEarlGrey waitForWebStateContainingText:kPage1];
+
+  // The omnibox shouldn't be focused and the popup should be closed.
+  [self checkLocationBarSteadyState];
+  [[EarlGrey
+      selectElementWithMatcher:
+          grey_accessibilityID(kOmniboxPopupTableViewAccessibilityIdentifier)]
+      assertWithMatcher:grey_notVisible()];
+}
+
+- (void)testOmniboxDefocusesOnTabSwitchIncognito {
+  [ChromeEarlGrey openNewIncognitoTab];
+  [ChromeEarlGrey waitForIncognitoTabCount:1];
+  [self openPage1];
+
+  [ChromeEarlGrey openNewIncognitoTab];
+  [ChromeEarlGrey waitForIncognitoTabCount:2];
+  [self openPage2];
+
+  [ChromeEarlGreyUI focusOmnibox];
+  [[EarlGrey selectElementWithMatcher:chrome_test_util::Omnibox()]
+      performAction:grey_typeText(@"Obama")];
+
+  // The popup should open.
+  [[EarlGrey
+      selectElementWithMatcher:
+          grey_accessibilityID(kOmniboxPopupTableViewAccessibilityIdentifier)]
+      assertWithMatcher:grey_notNil()];
+
+  // Switch to the first tab.
+  [ChromeEarlGrey selectTabAtIndex:0];
+  [ChromeEarlGrey waitForWebStateContainingText:kPage1];
+
+  // The omnibox shouldn't be focused and the popup should be closed.
+  [self checkLocationBarSteadyState];
+  [[EarlGrey
+      selectElementWithMatcher:
+          grey_accessibilityID(kOmniboxPopupTableViewAccessibilityIdentifier)]
+      assertWithMatcher:grey_notVisible()];
+}
+
 #pragma mark - Helpers
 
 // Navigates to Page 1 in a tab and waits for it to load.