[ios] Creates flag for Collections Automatic style presentation.

Bug: 979201
Change-Id: Iec61d3d7115b1aaeece301a501035a1f6df2b71b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1713812Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Commit-Queue: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#680212}

ios/chrome/browser/flags/BUILD.gn

@@ -51,6 +51,7 @@ source_set("flags") {
     "//ios/chrome/browser/ui/fullscreen:feature_flags",
     "//ios/chrome/browser/ui/infobars:feature_flags",
     "//ios/chrome/browser/ui/settings/autofill:feature_flags",
+    "//ios/chrome/browser/ui/table_view:feature_flags",
     "//ios/chrome/browser/ui/toolbar/public:feature_flags",
     "//ios/chrome/browser/ui/toolbar_container:feature_flags",
     "//ios/chrome/browser/web:feature_flags",

ios/chrome/browser/flags/about_flags.mm

@@ -62,6 +62,7 @@
 #import "ios/chrome/browser/ui/fullscreen/fullscreen_features.h"
 #import "ios/chrome/browser/ui/infobars/infobar_feature.h"
 #include "ios/chrome/browser/ui/settings/autofill/features.h"
+#import "ios/chrome/browser/ui/table_view/feature_flags.h"
 #import "ios/chrome/browser/ui/toolbar/public/features.h"
 #import "ios/chrome/browser/ui/toolbar_container/toolbar_container_features.h"
 #include "ios/chrome/browser/ui/ui_feature_flags.h"
@@ -578,6 +579,10 @@ const flags_ui::FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kSettingsAddPaymentMethodName,
      flag_descriptions::kSettingsAddPaymentMethodDescription, flags_ui::kOsIos,
      FEATURE_VALUE_TYPE(kSettingsAddPaymentMethod)},
+    {"collections-card-presentation-style",
+     flag_descriptions::kCollectionsCardPresentationStyleName,
+     flag_descriptions::kCollectionsCardPresentationStyleDescription,
+     flags_ui::kOsIos, FEATURE_VALUE_TYPE(kCollectionsCardPresentationStyle)},
 };
 
 // Add all switches from experimental flags to |command_line|.

ios/chrome/browser/flags/ios_chrome_flag_descriptions.cc

@@ -126,6 +126,12 @@ const char kClosingLastIncognitoTabDescription[] =
     "Automatically switches to the regular tabs panel in the tab grid after "
     "closing the last incognito tab";
 
+const char kCollectionsCardPresentationStyleName[] =
+    "Card style presentation for Collections.";
+const char kCollectionsCardPresentationStyleDescription[] =
+    "When enabled collections are presented using the new iOS13 card "
+    "style.";
+
 const char kContextualSearch[] = "Contextual Search";
 const char kContextualSearchDescription[] =
     "Whether or not Contextual Search is enabled.";

ios/chrome/browser/flags/ios_chrome_flag_descriptions.h

@@ -97,6 +97,11 @@ extern const char kBrowserTaskSchedulerDescription[];
 extern const char kClosingLastIncognitoTabName[];
 extern const char kClosingLastIncognitoTabDescription[];
 
+// Title and description for the flag that controls whether Collections are
+// presented using the new iOS13 Card style or the custom legacy one.
+extern const char kCollectionsCardPresentationStyleName[];
+extern const char kCollectionsCardPresentationStyleDescription[];
+
 // Title and description for the flag to enable Contextual Search.
 extern const char kContextualSearch[];
 extern const char kContextualSearchDescription[];

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

@@ -79,6 +79,17 @@ source_set("views") {
   ]
 }
 
+source_set("feature_flags") {
+  configs += [ "//build/config/compiler:enable_arc" ]
+  sources = [
+    "feature_flags.h",
+    "feature_flags.mm",
+  ]
+  deps = [
+    "//base",
+  ]
+}
+
 source_set("test_support") {
   configs += [ "//build/config/compiler:enable_arc" ]
   testonly = true

ios/chrome/browser/ui/table_view/feature_flags.h

+// Copyright 2019 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_TABLE_VIEW_FEATURE_FLAGS_H_
+#define IOS_CHROME_BROWSER_UI_TABLE_VIEW_FEATURE_FLAGS_H_
+
+#include "base/feature_list.h"
+
+// Feature to choose whether to use the new Card iOS13 presentation, or the
+// legacy one.
+extern const base::Feature kCollectionsCardPresentationStyle;
+
+// Whether the kCollectionsCardPresentationStyle flag is enabled.
+bool IsCollectionsCardPresentationStyleEnabled();
+
+#endif  // IOS_CHROME_BROWSER_UI_TABLE_VIEW_FEATURE_FLAGS_H_

ios/chrome/browser/ui/table_view/feature_flags.mm

+// Copyright 2019 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.
+
+#import "ios/chrome/browser/ui/table_view/feature_flags.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+const base::Feature kCollectionsCardPresentationStyle{
+    "CollectionsCardPresentationStyle", base::FEATURE_DISABLED_BY_DEFAULT};
+
+bool IsCollectionsCardPresentationStyleEnabled() {
+  return base::FeatureList::IsEnabled(kCollectionsCardPresentationStyle);
+}