[privacy_budget] Enable `gn check`.

Includes some fixes for issues found by `gn check` in the
`privacy_budget` directories.

Bug: 973801
Change-Id: Iad543786ea08108a165dc08fc6b7c7794e14f5e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2251090
Commit-Queue: Asanka Herath <asanka@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#782164}

.gn

@@ -166,6 +166,7 @@ check_targets = [
   "//chrome/browser/prerender/*",
   "//chrome/browser/previews/*",
   "//chrome/browser/printing/*",
+  "//chrome/browser/privacy_budget/*",
   "//chrome/browser/profile_resetter/*",
   "//chrome/browser/profiles/*",
 
@@ -344,6 +345,7 @@ check_targets = [
 
   # "//third_party/blink/*",  # Errors: https://crbug.com/800764
   "//third_party/blink/public/*",
+  "//third_party/blink/common/privacy_budget/*",
 
   #"//third_party/breakpad/*",  # Small errors.
   "//third_party/boringssl/*",

chrome/browser/privacy_budget/BUILD.gn

@@ -14,10 +14,13 @@ source_set("privacy_budget") {
 
   deps = [
     "//base",
+    "//chrome/common/privacy_budget",
+    "//components/prefs",
+    "//components/ukm",
     "//services/metrics/public/cpp:metrics_cpp",
     "//services/metrics/public/cpp:ukm_builders",
     "//services/metrics/public/mojom",
-    "//third_party/blink/public/common",
+    "//third_party/blink/public/common/privacy_budget",
   ]
 }
 
@@ -30,6 +33,7 @@ source_set("unit_tests") {
   ]
 
   deps = [
+    ":privacy_budget",
     "//chrome/common/privacy_budget:test_support",
     "//chrome/test:test_support",
     "//testing/gtest",

third_party/blink/common/privacy_budget/BUILD.gn

@@ -44,6 +44,7 @@ source_set("unit_tests") {
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/blink/public/common",
+    "//third_party/blink/public/common/privacy_budget:internal",
   ]
 }
 

third_party/blink/public/common/privacy_budget/BUILD.gn

@@ -2,9 +2,17 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+source_set("internal") {
+  sources = [ "identifiability_internal_templates.h" ]
+
+  visibility = [
+    ":*",
+    "//third_party/blink/common/privacy_budget:*",
+  ]
+}
+
 source_set("privacy_budget") {
   sources = [
-    "identifiability_internal_templates.h",
     "identifiability_metric_builder.h",
     "identifiability_metrics.h",
     "identifiability_study_participation.h",
@@ -16,13 +24,11 @@ source_set("privacy_budget") {
   ]
 
   deps = [
+    ":internal",
     "//base",
     "//services/metrics/public/cpp:metrics_cpp",
     "//services/network/public/cpp:cpp",
     "//third_party/blink/public/common:common_export",
     "//third_party/blink/public/mojom:web_feature_mojo_bindings",
   ]
-
-  # Internal templates are not a public API.
-  public = sources - [ "identifiability_internal_templates.h" ]
 }

third_party/blink/public/common/privacy_budget/identifiability_internal_templates.h

@@ -5,10 +5,10 @@
 #ifndef THIRD_PARTY_BLINK_PUBLIC_COMMON_PRIVACY_BUDGET_IDENTIFIABILITY_INTERNAL_TEMPLATES_H_
 #define THIRD_PARTY_BLINK_PUBLIC_COMMON_PRIVACY_BUDGET_IDENTIFIABILITY_INTERNAL_TEMPLATES_H_
 
+#include <cstdint>
+#include <cstring>
 #include <type_traits>
 
-#include "third_party/blink/public/common/privacy_budget/identifiability_metrics.h"
-
 namespace blink {
 
 namespace internal {
@@ -66,7 +66,7 @@ constexpr int64_t DigestOfObjectRepresentation(T in) {
     return in;
 
   int64_t result = 0;
-  memcpy(&result, &in, sizeof(in));
+  std::memcpy(&result, &in, sizeof(in));
   return result;
 }