[ios] Don't show a sad tab over the NTP.

Don't layer the sad tab overlay over the NTP, since it doesn't matter of the web
process bails for about://newtab.  Interestingly enough, this is a possible
outcome.

Bug: 932618
Change-Id: I9cc2afdb0e5ca6ac9de9a9e8ad91146574392e99
Reviewed-on: https://chromium-review.googlesource.com/c/1475793
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Auto-Submit: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#632729}

ios/chrome/browser/web/BUILD.gn

@@ -40,6 +40,7 @@ source_set("web") {
     "//ios/chrome/app/strings:ios_strings_grit",
     "//ios/chrome/browser",
     "//ios/chrome/browser/browser_state",
+    "//ios/chrome/browser/ntp",
     "//ios/chrome/browser/snapshots",
     "//ios/chrome/browser/ui",
     "//ios/chrome/browser/ui/commands:commands",
@@ -105,7 +106,9 @@ source_set("unit_tests") {
     "//components/search_engines",
     "//components/services/unzip/public/interfaces",
     "//components/strings:components_strings_grit",
+    "//ios/chrome/browser",
     "//ios/chrome/browser/browser_state:test_support",
+    "//ios/chrome/browser/ntp",
     "//ios/chrome/browser/snapshots",
     "//ios/chrome/test:test_support",
     "//ios/net:test_support",

ios/chrome/browser/web/sad_tab_tab_helper.mm

@@ -14,6 +14,7 @@
 #include "base/strings/sys_string_conversions.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
 #include "ios/chrome/browser/chrome_url_constants.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
 #include "ios/chrome/browser/ui/fullscreen/fullscreen_controller_factory.h"
 #include "ios/chrome/browser/ui/fullscreen/scoped_fullscreen_disabler.h"
 #import "ios/chrome/browser/web/page_placeholder_tab_helper.h"
@@ -102,6 +103,13 @@ void SadTabTabHelper::WasHidden(web::WebState* web_state) {
 
 void SadTabTabHelper::RenderProcessGone(web::WebState* web_state) {
   DCHECK_EQ(web_state_, web_state);
+
+  // Don't present a sad tab on top of an NTP.
+  NewTabPageTabHelper* NTPHelper = NewTabPageTabHelper::FromWebState(web_state);
+  if (NTPHelper && NTPHelper->IsActive()) {
+    return;
+  }
+
   if (!web_state->IsVisible()) {
     requires_reload_on_becoming_visible_ = true;
     return;

ios/chrome/browser/web/sad_tab_tab_helper_unittest.mm

@@ -8,6 +8,9 @@
 
 #include "base/test/scoped_task_environment.h"
 #include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
+#include "ios/chrome/browser/chrome_url_constants.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper.h"
+#import "ios/chrome/browser/ntp/new_tab_page_tab_helper_delegate.h"
 #import "ios/chrome/browser/web/page_placeholder_tab_helper.h"
 #import "ios/chrome/browser/web/sad_tab_tab_helper_delegate.h"
 #import "ios/web/public/test/fakes/fake_navigation_context.h"
@@ -142,6 +145,25 @@ TEST_F(SadTabTabHelperTest, AppInBackground) {
   EXPECT_TRUE(navigation_manager_->LoadIfNecessaryWasCalled());
 }
 
+// Tests that SadTab is not presented if app is displaying the NTP.
+TEST_F(SadTabTabHelperTest, AppOnNTP) {
+  web_state_.WasShown();
+
+  web_state_.SetVisibleURL(GURL(kChromeUINewTabURL));
+  id delegate = OCMProtocolMock(@protocol(NewTabPageTabHelperDelegate));
+  NewTabPageTabHelper::CreateForWebState(&web_state_, delegate);
+
+  // Delegate and TabHelper should not present a SadTab.
+  EXPECT_FALSE(tab_helper()->is_showing_sad_tab());
+  EXPECT_FALSE(sad_tab_delegate_.showingSadTab);
+
+  // Helper should get notified of render process failure,
+  // but Sad Tab should not be presented, because application is on the NTP.
+  web_state_.OnRenderProcessGone();
+  EXPECT_FALSE(tab_helper()->is_showing_sad_tab());
+  EXPECT_FALSE(sad_tab_delegate_.showingSadTab);
+}
+
 // Tests that SadTab is not presented if app is in inactive  and navigation
 // item is reloaded once the app became active.
 TEST_F(SadTabTabHelperTest, AppIsInactive) {