add brave://flags feature to enable cosmetic filtering

chromium_src/chrome/browser/about_flags.cc

@@ -3,6 +3,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#define BRAVE_FEATURE_ENTRIES \
+    {"brave-adblock-cosmetic-filtering",                                   \
+     flag_descriptions::kBraveAdblockCosmeticFilteringName,                \
+     flag_descriptions::kBraveAdblockCosmeticFilteringDescription, kOsAll, \
+     FEATURE_VALUE_TYPE(features::kBraveAdblockCosmeticFiltering)},
+
 #define SetFeatureEntryEnabled SetFeatureEntryEnabled_ChromiumImpl
 #include "../../../../chrome/browser/about_flags.cc"       // NOLINT
 #include "../../../../components/flags_ui/flags_state.cc"  // NOLINT

chromium_src/chrome/browser/flag_descriptions.cc

@@ -0,0 +1,12 @@
+/* Copyright (c) 2019 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "../../../../chrome/browser/flag_descriptions.cc"
+
+namespace flag_descriptions {
+const char kBraveAdblockCosmeticFilteringName[] = "Enable cosmetic filtering";
+const char kBraveAdblockCosmeticFilteringDescription[] =
+    "Enable support for cosmetic filtering";
+}

chromium_src/chrome/browser/flag_descriptions.h

@@ -0,0 +1,16 @@
+/* Copyright (c) 2019 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FLAG_DESCRIPTIONS_H_
+#define BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FLAG_DESCRIPTIONS_H_
+
+#include "../../../../chrome/browser/flag_descriptions.h"
+
+namespace flag_descriptions {
+extern const char kBraveAdblockCosmeticFilteringName[];
+extern const char kBraveAdblockCosmeticFilteringDescription[];
+}
+
+#endif  // BRAVE_CHROMIUM_SRC_CHROME_BROWSER_FLAG_DESCRIPTIONS_H_

chromium_src/chrome/common/chrome_features.cc

@@ -0,0 +1,12 @@
+/* Copyright (c) 2019 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "../../../../chrome/common/chrome_features.cc"
+
+namespace features {
+const base::Feature kBraveAdblockCosmeticFiltering{
+    "BraveAdblockCosmeticFiltering",
+    base::FEATURE_DISABLED_BY_DEFAULT};
+}

chromium_src/chrome/common/chrome_features.h

@@ -0,0 +1,16 @@
+/* Copyright (c) 2019 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BRAVE_CHROMIUM_SRC_CHROME_COMMON_CHROME_FEATURES_H_
+#define BRAVE_CHROMIUM_SRC_CHROME_COMMON_CHROME_FEATURES_H_
+
+#include "../../../../chrome/common/chrome_features.h"
+
+namespace features {
+COMPONENT_EXPORT(CHROME_FEATURES)
+extern const base::Feature kBraveAdblockCosmeticFiltering;
+}
+
+#endif  // BRAVE_CHROMIUM_SRC_CHROME_COMMON_CHROME_FEATURES_H_

patches/chrome-browser-about_flags.cc.patch

@@ -21,3 +21,11 @@ index 0ab55be2f96853137cec8928621360e9f639b467..34e01378c8e413af12399bc3ca30188b
 
  const FeatureEntry::Choice kPassiveListenersChoices[] = {
      {flags_ui::kGenericExperimentChoiceDefault, "", ""},
+@@ -4688,6 +4688,7 @@ const FeatureEntry kFeatureEntries[] = {
+     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
+     // Histograms" in tools/metrics/histograms/README.md (run the
+     // AboutFlagsHistogramTest unit test to verify this process).
++    BRAVE_FEATURE_ENTRIES
+ };
+
+ class FlagsStateSingleton {