[UI Refresh] Support special cases for the incognito NTP location bar.

Adds a special treatment for the Incognito NTP: the share button is now
hidden, and there is a fake "placeholder" in the steady view.

Bug: 845956
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I761ff6d418b49527afb04ce890ca09a481e39778
Reviewed-on: https://chromium-review.googlesource.com/1095111
Commit-Queue: Stepan Khapugin <stkhapugin@chromium.org>
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#566833}

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

@@ -16,6 +16,10 @@
 // Notifies consumer to defocus the omnibox (for example on tab change).
 - (void)defocusOmnibox;
 
+// Notifies the consumer to update after a navigation to NTP. Will be called
+// after -updateLocationText. Used for triggering NTP-specific location bar UI.
+- (void)updateAfterNavigatingToNTP;
+
 @end
 
 #endif  // IOS_CHROME_BROWSER_UI_LOCATION_BAR_LOCATION_BAR_CONSUMER_H_

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

@@ -273,6 +273,7 @@ const int kLocationAuthorizationStatusCount = 4;
 - (void)updateLocationText:(NSString*)text {
   [self.omniboxCoordinator updateOmniboxState];
   [self.viewController updateLocationText:text];
+  [self.viewController updateForIncognitoNTP:NO];
 }
 
 - (void)defocusOmnibox {
@@ -283,6 +284,13 @@ const int kLocationAuthorizationStatusCount = 4;
   [self.viewController updateLocationIcon:icon];
 }
 
+- (void)updateAfterNavigatingToNTP {
+  BOOL isIncognito = self.browserState->IsOffTheRecord();
+  if (isIncognito) {
+    [self.viewController updateForIncognitoNTP:YES];
+  }
+}
+
 #pragma mark - private
 
 // Returns a dictionary with variation headers for qualified URLs. Can be empty.

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

@@ -78,20 +78,20 @@
 
 - (void)webState:(web::WebState*)webState didLoadPageWithSuccess:(BOOL)success {
   DCHECK_EQ(_webState, webState);
-  [self.consumer updateLocationText:[self currentLocationString]];
+  [self notifyConsumerOfChangedLocation];
 }
 
 - (void)webState:(web::WebState*)webState
     didStartNavigation:(web::NavigationContext*)navigation {
   DCHECK_EQ(_webState, webState);
-  [self.consumer updateLocationText:[self currentLocationString]];
+  [self notifyConsumerOfChangedLocation];
   [self notifyConsumerOfChangedSecurityIcon];
 }
 
 - (void)webState:(web::WebState*)webState
     didFinishNavigation:(web::NavigationContext*)navigation {
   DCHECK_EQ(_webState, webState);
-  [self.consumer updateLocationText:[self currentLocationString]];
+  [self notifyConsumerOfChangedLocation];
   [self notifyConsumerOfChangedSecurityIcon];
 }
 
@@ -102,13 +102,13 @@
 
 - (void)webStateDidStartLoading:(web::WebState*)webState {
   DCHECK_EQ(_webState, webState);
-  [self.consumer updateLocationText:[self currentLocationString]];
+  [self notifyConsumerOfChangedLocation];
   [self notifyConsumerOfChangedSecurityIcon];
 }
 
 - (void)webStateDidStopLoading:(web::WebState*)webState {
   DCHECK_EQ(_webState, webState);
-  [self.consumer updateLocationText:[self currentLocationString]];
+  [self notifyConsumerOfChangedLocation];
   [self notifyConsumerOfChangedSecurityIcon];
 }
 
@@ -148,7 +148,7 @@
     _webState->AddObserver(_webStateObserver.get());
 
     if (self.consumer) {
-      [self.consumer updateLocationText:[self currentLocationString]];
+      [self notifyConsumerOfChangedLocation];
       [self notifyConsumerOfChangedSecurityIcon];
     }
   }
@@ -157,7 +157,7 @@
 - (void)setConsumer:(id<LocationBarConsumer>)consumer {
   _consumer = consumer;
   if (self.webState) {
-    [self.consumer updateLocationText:[self currentLocationString]];
+    [self notifyConsumerOfChangedLocation];
     [self notifyConsumerOfChangedSecurityIcon];
   }
 }
@@ -174,6 +174,15 @@
 
 #pragma mark - private
 
+- (void)notifyConsumerOfChangedLocation {
+  [self.consumer updateLocationText:[self currentLocationString]];
+  GURL URL = self.webState->GetVisibleURL();
+  BOOL isNTP = URL.GetOrigin() == kChromeUINewTabURL;
+  if (isNTP) {
+    [self.consumer updateAfterNavigatingToNTP];
+  }
+}
+
 - (void)notifyConsumerOfChangedSecurityIcon {
   [self.consumer updateLocationIcon:[self currentLocationIcon]];
 }

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

@@ -56,6 +56,10 @@
 - (void)updateLocationIcon:(UIImage*)icon;
 // Updates the location text in the non-editing mode.
 - (void)updateLocationText:(NSString*)text;
+// Updates the location view to show a fake placeholder in the steady location
+// view and hides the trailing button if |isIncognitoNTP|. Otherwise, shows the
+// location text and the button as normal.
+- (void)updateForIncognitoNTP:(BOOL)isIncognitoNTP;
 
 // Displays the voice search button instead of the share button in steady state,
 // and adds the voice search button to the empty textfield.

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

@@ -4,6 +4,7 @@
 
 #import "ios/chrome/browser/ui/location_bar/location_bar_view_controller.h"
 
+#include "components/strings/grit/components_strings.h"
 #import "ios/chrome/browser/ui/commands/activity_service_commands.h"
 #import "ios/chrome/browser/ui/commands/application_commands.h"
 #import "ios/chrome/browser/ui/commands/browser_commands.h"
@@ -11,6 +12,7 @@
 #include "ios/chrome/browser/ui/location_bar/location_bar_steady_view.h"
 #import "ios/chrome/browser/ui/util/constraints_ui_util.h"
 #import "ios/chrome/browser/ui/util/named_guide.h"
+#include "ui/base/l10n/l10n_util.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
@@ -35,6 +37,11 @@ typedef NS_ENUM(int, TrailingButtonState) {
 
 @property(nonatomic, assign) TrailingButtonState trailingButtonState;
 
+// When this flag is YES, the share button will not be displayed in situations
+// when it normally is shown. Setting it triggers a refresh of the button
+// visibility.
+@property(nonatomic, assign) BOOL hideShareButtonWhileOnIncognitoNTP;
+
 // Starts voice search, updating the NamedGuide to be constrained to the
 // trailing button.
 - (void)startVoiceSearch;
@@ -49,6 +56,8 @@ typedef NS_ENUM(int, TrailingButtonState) {
 @synthesize dispatcher = _dispatcher;
 @synthesize voiceSearchEnabled = _voiceSearchEnabled;
 @synthesize trailingButtonState = _trailingButtonState;
+@synthesize hideShareButtonWhileOnIncognitoNTP =
+    _hideShareButtonWhileOnIncognitoNTP;
 
 #pragma mark - public
 
@@ -95,10 +104,18 @@ typedef NS_ENUM(int, TrailingButtonState) {
     return;
   }
   _voiceSearchEnabled = enabled;
+  [self updateTrailingButtonState];
+}
+
+- (void)setHideShareButtonWhileOnIncognitoNTP:(BOOL)hide {
+  if (_hideShareButtonWhileOnIncognitoNTP == hide) {
+    return;
+  }
+  _hideShareButtonWhileOnIncognitoNTP = hide;
   [self updateTrailingButton];
 }
 
-- (void)updateTrailingButton {
+- (void)updateTrailingButtonState {
   BOOL shouldShowVoiceSearch =
       self.traitCollection.horizontalSizeClass ==
           UIUserInterfaceSizeClassRegular ||
@@ -134,7 +151,7 @@ typedef NS_ENUM(int, TrailingButtonState) {
 }
 
 - (void)traitCollectionDidChange:(UITraitCollection*)previousTraitCollection {
-  [self updateTrailingButton];
+  [self updateTrailingButtonState];
   [super traitCollectionDidChange:previousTraitCollection];
 }
 
@@ -183,17 +200,28 @@ typedef NS_ENUM(int, TrailingButtonState) {
       [icon imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
 }
 
+- (void)updateForIncognitoNTP:(BOOL)isIncognitoNTP {
+  if (isIncognitoNTP) {
+    // Display a fake "placeholder".
+    NSString* placeholderString =
+        l10n_util::GetNSString(IDS_OMNIBOX_EMPTY_HINT);
+    UIColor* placeholderColor =
+        [LocationBarSteadyViewColorScheme incognitoScheme].placeholderColor;
+    self.locationBarSteadyView.locationLabel.attributedText = [
+        [NSAttributedString alloc]
+        initWithString:placeholderString
+            attributes:@{NSForegroundColorAttributeName : placeholderColor}];
+  }
+  self.hideShareButtonWhileOnIncognitoNTP = isIncognitoNTP;
+}
+
 #pragma mark - private
 
 - (void)locationBarSteadyViewTapped {
   [self.delegate locationBarSteadyViewTapped];
 }
 
-- (void)setTrailingButtonState:(TrailingButtonState)state {
-  if (_trailingButtonState == state) {
-    return;
-  }
-
+- (void)updateTrailingButton {
   // Stop constraining the voice guide to the trailing button if transitioning
   // from kVoiceSearchButton.
   NamedGuide* voiceGuide =
@@ -202,7 +230,6 @@ typedef NS_ENUM(int, TrailingButtonState) {
   if (voiceGuide.constrainedView == self.locationBarSteadyView.trailingButton)
     voiceGuide.constrainedView = nil;
 
-  _trailingButtonState = state;
 
   // Cancel previous possible state.
   [self.locationBarSteadyView.trailingButton
@@ -211,6 +238,11 @@ typedef NS_ENUM(int, TrailingButtonState) {
       forControlEvents:UIControlEventAllEvents];
   self.locationBarSteadyView.trailingButton.hidden = NO;
 
+  TrailingButtonState state = self.trailingButtonState;
+  if (state == kShareButton && self.hideShareButtonWhileOnIncognitoNTP) {
+    state = kNoButton;
+  }
+
   switch (state) {
     case kNoButton: {
       self.locationBarSteadyView.trailingButton.hidden = YES;
@@ -247,6 +279,15 @@ typedef NS_ENUM(int, TrailingButtonState) {
   }
 }
 
+- (void)setTrailingButtonState:(TrailingButtonState)state {
+  if (_trailingButtonState == state) {
+    return;
+  }
+  _trailingButtonState = state;
+
+  [self updateTrailingButton];
+}
+
 - (void)startVoiceSearch {
   [NamedGuide guideWithName:kVoiceSearchButtonGuide view:self.view]
       .constrainedView = self.locationBarSteadyView.trailingButton;