[ios] Persist Crash Restore flag

Add a feature flag to encapsulate logic that will persist the crash
restore infobar across navigations.

Bug: 1162312
Change-Id: I70c00d3ebe8d382c4406286da18a49b608c6744e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2606625
Commit-Queue: Chris Lu <thegreenfrog@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#839681}

chrome/browser/flag-metadata.json

@@ -3100,6 +3100,11 @@
     "owners": [ "livvielin", "bling-flags@google.com" ],
     "expiry_milestone": 89
   },
+  {
+    "name": "ios-persist-crash-restore-infobar",
+    "owners": [ "thegreenfrog", "bling-flags@google.com" ],
+    "expiry_milestone": 91
+  },
   {
     "name": "ios-shared-highlighting-color-change",
     "owners": [ "cheickcisse" ],

ios/chrome/browser/crash_report/BUILD.gn

@@ -76,6 +76,7 @@ source_set("crash_report_internal") {
     "//ios/chrome/browser/sessions:restoration_agent",
     "//ios/chrome/browser/sessions:serialisation",
     "//ios/chrome/browser/sessions:session_service",
+    "//ios/chrome/browser/ui:feature_flags",
     "//ios/chrome/browser/ui/main:scene_state_header",
     "//ios/chrome/browser/ui/util:multiwindow_util",
     "//ios/chrome/browser/web:tab_id_tab_helper",

ios/chrome/browser/crash_report/crash_restore_helper.mm

@@ -7,6 +7,7 @@
 #include <memory>
 #include <utility>
 
+#include "base/feature_list.h"
 #include "base/metrics/histogram_functions.h"
 #include "base/metrics/user_metrics.h"
 #include "base/metrics/user_metrics_action.h"
@@ -35,6 +36,7 @@
 #import "ios/chrome/browser/sessions/session_window_ios.h"
 #import "ios/chrome/browser/ui/main/scene_state.h"
 #import "ios/chrome/browser/ui/main/scene_state_browser_agent.h"
+#include "ios/chrome/browser/ui/ui_feature_flags.h"
 #import "ios/chrome/browser/ui/util/multi_window_support.h"
 #include "ios/chrome/browser/web_state_list/web_state_list.h"
 #include "ios/chrome/grit/ios_theme_resources.h"
@@ -141,6 +143,7 @@ class SessionCrashedInfoBarDelegate : public ConfirmInfoBarDelegate {
   base::string16 GetButtonLabel(InfoBarButton button) const override;
   bool Accept() override;
   void InfoBarDismissed() override;
+  bool ShouldExpire(const NavigationDetails& details) const override;
   int GetIconId() const override;
 
   // TimeInterval when the delegate was created.
@@ -215,6 +218,15 @@ void SessionCrashedInfoBarDelegate::InfoBarDismissed() {
           forInfobarConfirmType:InfobarConfirmType::kInfobarConfirmTypeRestore];
 }
 
+bool SessionCrashedInfoBarDelegate::ShouldExpire(
+    const NavigationDetails& details) const {
+  if (base::FeatureList::IsEnabled(kIOSPersistCrashRestore)) {
+    return false;
+  } else {
+    return InfoBarDelegate::ShouldExpire(details);
+  }
+}
+
 int SessionCrashedInfoBarDelegate::GetIconId() const {
   return IDR_IOS_INFOBAR_RESTORE_SESSION;
 }

ios/chrome/browser/flags/about_flags.mm

@@ -583,6 +583,10 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kIOSSharedHighlightingColorChangeName,
      flag_descriptions::kIOSSharedHighlightingColorChangeDescription,
      flags_ui::kOsIos, FEATURE_VALUE_TYPE(kIOSSharedHighlightingColorChange)},
+    {"ios-persist-crash-restore-infobar",
+     flag_descriptions::kIOSPersistCrashRestoreName,
+     flag_descriptions::kIOSPersistCrashRestoreDescription, flags_ui::kOsIos,
+     FEATURE_VALUE_TYPE(kIOSPersistCrashRestore)},
 };
 
 bool SkipConditionalFeatureEntry(const flags_ui::FeatureEntry& entry) {

ios/chrome/browser/flags/ios_chrome_flag_descriptions.cc

@@ -265,6 +265,11 @@ const char kIOSLegacyTLSInterstitialsDescription[] =
     "that use legacy TLS connections, and subresources using legacy TLS "
     "connections will be blocked.";
 
+const char kIOSPersistCrashRestoreName[] = "Persist Crash Restore Infobar";
+const char kIOSPersistCrashRestoreDescription[] =
+    "When enabled, the Crash Restore Infobar will persist through navigations "
+    "instead of dismissing.";
+
 const char kIOSSharedHighlightingColorChangeName[] =
     "IOS Shared Highlighting color change";
 const char kIOSSharedHighlightingColorChangeDescription[] =

ios/chrome/browser/flags/ios_chrome_flag_descriptions.h

@@ -227,6 +227,11 @@ extern const char kInProductHelpDemoModeDescription[];
 extern const char kIOSLegacyTLSInterstitialsName[];
 extern const char kIOSLegacyTLSInterstitialsDescription[];
 
+// Title and description for the flag to persist the Crash Restore Infobar
+// across navigations.
+extern const char kIOSPersistCrashRestoreName[];
+extern const char kIOSPersistCrashRestoreDescription[];
+
 // Title and description for the flag to enable Shared Highlighting color
 // change in iOS.
 extern const char kIOSSharedHighlightingColorChangeName[];

ios/chrome/browser/ui/ui_feature_flags.cc

@@ -69,3 +69,6 @@ const base::Feature kDefaultBrowserFullscreenPromoExperiment{
 
 const base::Feature kIOSSharedHighlightingColorChange{
     "IOSSharedHighlightingColorChange", base::FEATURE_DISABLED_BY_DEFAULT};
+
+const base::Feature kIOSPersistCrashRestore{"IOSPersistCrashRestore",
+                                            base::FEATURE_DISABLED_BY_DEFAULT};

ios/chrome/browser/ui/ui_feature_flags.h

@@ -74,4 +74,8 @@ extern const base::Feature kDefaultBrowserFullscreenPromoExperiment;
 // Feature flag that enable Shared Highlighting color change in iOS.
 extern const base::Feature kIOSSharedHighlightingColorChange;
 
+// Feature flag that enables persisting the Crash Restore Infobar across
+// navigations.
+extern const base::Feature kIOSPersistCrashRestore;
+
 #endif  // IOS_CHROME_BROWSER_UI_UI_FEATURE_FLAGS_H_