{M103 PICK} [Fix UserAgentReduction Policy] (2) Fix GetProductAndVersion

This resolves an issue where the user agent reduction enterprise policy
is not respected due to GetProductAndVersion only checking the feature.
The policy is propagated from
ChromeContentBrowserClient::GetUserAgentBasedOnPolicy downward.
The specific issue is tested in UserAgentUtilsTest::GetProductAndVersion
under item 4c (policy force disabled overrides the feature being
enabled).

This CL is part of a series:
(1) Make ForceMajorVersionToMinorPosition a class enum
(2) Fix GetProductAndVersion

(cherry picked from commit 8bb92c3)

Bug: 1330588
Change-Id: I6f2dfcf8ea9e9c217c1562f4efca2df24de613f9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3684269
Auto-Submit: Ari Chivukula <arichiv@chromium.org>
Reviewed-by: Victor Tan <victortan@chromium.org>
Commit-Queue: Ari Chivukula <arichiv@chromium.org>
Quick-Run: Ari Chivukula <arichiv@chromium.org>
Cr-Original-Commit-Position: refs/heads/main@{#1010140}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3687390
Cr-Commit-Position: refs/branch-heads/5060@{#636}
Cr-Branched-From: b83393d-refs/heads/main@{#1002911}

chrome/browser/chrome_content_browser_client.cc

@@ -1364,7 +1364,8 @@ void ChromeContentBrowserClient::RegisterProfilePrefs(
       enterprise::content::kCopyPreventionSettings);
   registry->RegisterIntegerPref(
       prefs::kUserAgentReduction,
-      UserAgentReductionEnterprisePolicyState::kDefault);
+      static_cast<int>(
+          embedder_support::UserAgentReductionEnterprisePolicyState::kDefault));
   registry->RegisterBooleanPref(prefs::kOriginAgentClusterDefaultEnabled, true);
   registry->RegisterIntegerPref(
       prefs::kForceMajorVersionToMinorPositionInUserAgent,
@@ -5913,18 +5914,26 @@ std::string ChromeContentBrowserClient::GetUserAgent() {
 
 std::string ChromeContentBrowserClient::GetUserAgentBasedOnPolicy(
     content::BrowserContext* context) {
+  const PrefService* prefs = Profile::FromBrowserContext(context)->GetPrefs();
   embedder_support::ForceMajorVersionToMinorPosition
-      force_major_version_to_minor = embedder_support::GetMajorToMinorFromPrefs(
-          Profile::FromBrowserContext(context)->GetPrefs());
-  switch (GetUserAgentReductionEnterprisePolicyState(context)) {
-    case UserAgentReductionEnterprisePolicyState::kForceDisabled:
-      return embedder_support::GetFullUserAgent(force_major_version_to_minor);
-    case UserAgentReductionEnterprisePolicyState::kForceEnabled:
+      force_major_version_to_minor =
+          embedder_support::GetMajorToMinorFromPrefs(prefs);
+  embedder_support::UserAgentReductionEnterprisePolicyState
+      user_agent_reduction =
+          embedder_support::GetUserAgentReductionFromPrefs(prefs);
+  switch (user_agent_reduction) {
+    case embedder_support::UserAgentReductionEnterprisePolicyState::
+        kForceDisabled:
+      return embedder_support::GetFullUserAgent(force_major_version_to_minor,
+                                                user_agent_reduction);
+    case embedder_support::UserAgentReductionEnterprisePolicyState::
+        kForceEnabled:
       return embedder_support::GetReducedUserAgent(
           force_major_version_to_minor);
-    case UserAgentReductionEnterprisePolicyState::kDefault:
+    case embedder_support::UserAgentReductionEnterprisePolicyState::kDefault:
     default:
-      return embedder_support::GetUserAgent(force_major_version_to_minor);
+      return embedder_support::GetUserAgent(force_major_version_to_minor,
+                                            user_agent_reduction);
   }
 }
 
@@ -6477,23 +6486,6 @@ bool ChromeContentBrowserClient::ShouldPreconnectNavigation(
       *Profile::FromBrowserContext(browser_context)->GetPrefs());
 }
 
-ChromeContentBrowserClient::UserAgentReductionEnterprisePolicyState
-ChromeContentBrowserClient::GetUserAgentReductionEnterprisePolicyState(
-    content::BrowserContext* context) {
-  int policy = Profile::FromBrowserContext(context)->GetPrefs()->GetInteger(
-      prefs::kUserAgentReduction);
-  switch (policy) {
-    case 0:
-      return UserAgentReductionEnterprisePolicyState::kDefault;
-    case 1:
-      return UserAgentReductionEnterprisePolicyState::kForceDisabled;
-    case 2:
-      return UserAgentReductionEnterprisePolicyState::kForceEnabled;
-  }
-
-  return UserAgentReductionEnterprisePolicyState::kDefault;
-}
-
 bool ChromeContentBrowserClient::ShouldDisableOriginAgentClusterDefault(
     content::BrowserContext* browser_context) {
   // The enterprise policy for kOriginAgentClusterDefaultEnabled defaults to

chrome/browser/chrome_content_browser_client.h

@@ -784,12 +784,6 @@ class ChromeContentBrowserClient : public content::ContentBrowserClient {
   bool ShouldPreconnectNavigation(
       content::BrowserContext* browser_context) override;
 
-  enum UserAgentReductionEnterprisePolicyState {
-    kDefault = 0,
-    kForceDisabled = 1,
-    kForceEnabled = 2,
-  };
-
   bool ShouldDisableOriginAgentClusterDefault(
       content::BrowserContext* browser_context) override;
 
@@ -889,9 +883,6 @@ class ChromeContentBrowserClient : public content::ContentBrowserClient {
       std::unique_ptr<ScopedKeepAlive> keep_alive_handle);
 #endif
 
-  UserAgentReductionEnterprisePolicyState
-  GetUserAgentReductionEnterprisePolicyState(content::BrowserContext* context);
-
   // Vector of additional ChromeContentBrowserClientParts.
   // Parts are deleted in the reverse order they are added.
   std::vector<ChromeContentBrowserClientParts*> extra_parts_;

chrome/browser/user_agent/user_agent_browsertest.cc

@@ -24,7 +24,7 @@
 namespace policy {
 
 using ReductionPolicyState =
-    ChromeContentBrowserClient::UserAgentReductionEnterprisePolicyState;
+    embedder_support::UserAgentReductionEnterprisePolicyState;
 using ForceMajorVersionToMinorPolicyState =
     embedder_support::ForceMajorVersionToMinorPosition;
 
@@ -48,14 +48,15 @@ class UserAgentBrowserTest : public InProcessBrowserTest,
     InProcessBrowserTest::SetUp();
   }
 
-  void set_user_agent_reduction_policy(int policy) {
+  void set_user_agent_reduction_policy(ReductionPolicyState policy) {
     browser()->profile()->GetPrefs()->SetInteger(prefs::kUserAgentReduction,
-                                                 policy);
+                                                 static_cast<int>(policy));
   }
 
-  int user_agent_reduction_policy() {
-    return browser()->profile()->GetPrefs()->GetInteger(
-        prefs::kUserAgentReduction);
+  ReductionPolicyState user_agent_reduction_policy() {
+    return static_cast<ReductionPolicyState>(
+        browser()->profile()->GetPrefs()->GetInteger(
+            prefs::kUserAgentReduction));
   }
 
   void set_force_major_version_to_minor_policy(
@@ -90,7 +91,11 @@ IN_PROC_BROWSER_TEST_P(UserAgentBrowserTest, EnterprisePolicyInitialized) {
 IN_PROC_BROWSER_TEST_P(UserAgentBrowserTest, ReductionPolicyDisabled) {
   set_user_agent_reduction_policy(ReductionPolicyState::kForceDisabled);
   ASSERT_TRUE(ui_test_utils::NavigateToURL(browser(), empty_url()));
-  EXPECT_EQ(observed_user_agent(), embedder_support::GetFullUserAgent());
+  EXPECT_EQ(observed_user_agent(),
+            embedder_support::GetFullUserAgent(
+                embedder_support::ForceMajorVersionToMinorPosition::kDefault,
+                embedder_support::UserAgentReductionEnterprisePolicyState::
+                    kForceDisabled));
 }
 
 IN_PROC_BROWSER_TEST_P(UserAgentBrowserTest, ReductionPolicyEnabled) {

components/embedder_support/pref_names.cc

@@ -15,4 +15,8 @@ const char kAlternateErrorPagesEnabled[] = "alternate_error_pages.enabled";
 const char kForceMajorVersionToMinorPosition[] =
     "force_major_version_to_minor_position_in_user_agent";
 
+// Enum indicating if the user agent reduction feature should be forced enabled
+// or disabled. Defaults to blink::features::kReduceUserAgentMinorVersion trial.
+const char kReduceUserAgentMinorVersion[] = "user_agent_reduction";
+
 }  // namespace embedder_support

components/embedder_support/pref_names.h

@@ -12,6 +12,7 @@ namespace embedder_support {
 
 extern const char kAlternateErrorPagesEnabled[];
 extern const char kForceMajorVersionToMinorPosition[];
+extern const char kReduceUserAgentMinorVersion[];
 
 }  // namespace embedder_support
 

components/embedder_support/user_agent_utils.cc

@@ -173,6 +173,18 @@ bool ShouldForceMajorVersionToMinorPosition(
       force_major_to_minor == ForceMajorVersionToMinorPosition::kForceEnabled);
 }
 
+// Returns true if the user agent reduction should be forced (or prevented).
+// TODO(crbug.com/1330890): Remove this method along with policy.
+bool ShouldReduceUserAgentMinorVersion(
+    UserAgentReductionEnterprisePolicyState user_agent_reduction) {
+  return ((user_agent_reduction !=
+               UserAgentReductionEnterprisePolicyState::kForceDisabled &&
+           base::FeatureList::IsEnabled(
+               blink::features::kReduceUserAgentMinorVersion)) ||
+          user_agent_reduction ==
+              UserAgentReductionEnterprisePolicyState::kForceEnabled);
+}
+
 const std::string& GetMajorInMinorVersionNumber() {
   static const base::NoDestructor<std::string> version_number([] {
     base::Version version(version_info::GetVersionNumber());
@@ -330,18 +342,17 @@ std::string GetMajorVersionForUserAgentString(
 }  // namespace
 
 std::string GetProductAndVersion(
-    ForceMajorVersionToMinorPosition force_major_to_minor) {
+    ForceMajorVersionToMinorPosition force_major_to_minor,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction) {
   if (ShouldForceMajorVersionToMinorPosition(force_major_to_minor)) {
     // Force major version to 99 and major version to minor version position.
-    if (base::FeatureList::IsEnabled(
-            blink::features::kReduceUserAgentMinorVersion)) {
+    if (ShouldReduceUserAgentMinorVersion(user_agent_reduction)) {
       return "Chrome/" + GetReducedMajorInMinorVersionNumber();
     } else {
       return "Chrome/" + GetMajorInMinorVersionNumber();
     }
   } else {
-    if (base::FeatureList::IsEnabled(
-            blink::features::kReduceUserAgentMinorVersion)) {
+    if (ShouldReduceUserAgentMinorVersion(user_agent_reduction)) {
       return version_info::GetProductNameAndVersionForReducedUserAgent(
           blink::features::kUserAgentFrozenBuildVersion.Get().data());
     } else {
@@ -351,7 +362,8 @@ std::string GetProductAndVersion(
 }
 
 std::string GetUserAgent(
-    ForceMajorVersionToMinorPosition force_major_to_minor) {
+    ForceMajorVersionToMinorPosition force_major_to_minor,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction) {
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(kUserAgent)) {
     std::string ua = command_line->GetSwitchValueASCII(kUserAgent);
@@ -366,7 +378,7 @@ std::string GetUserAgent(
   if (base::FeatureList::IsEnabled(blink::features::kReduceUserAgent))
     return GetReducedUserAgent(force_major_to_minor);
 
-  return GetFullUserAgent(force_major_to_minor);
+  return GetFullUserAgent(force_major_to_minor, user_agent_reduction);
 }
 
 std::string GetReducedUserAgent(
@@ -378,8 +390,10 @@ std::string GetReducedUserAgent(
 }
 
 std::string GetFullUserAgent(
-    ForceMajorVersionToMinorPosition force_major_to_minor) {
-  std::string product = GetProductAndVersion(force_major_to_minor);
+    ForceMajorVersionToMinorPosition force_major_to_minor,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction) {
+  std::string product =
+      GetProductAndVersion(force_major_to_minor, user_agent_reduction);
 #if BUILDFLAG(IS_ANDROID)
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kUseMobileUserAgent))
@@ -615,4 +629,19 @@ embedder_support::ForceMajorVersionToMinorPosition GetMajorToMinorFromPrefs(
   }
 }
 
+embedder_support::UserAgentReductionEnterprisePolicyState
+GetUserAgentReductionFromPrefs(const PrefService* pref_service) {
+  if (!pref_service->HasPrefPath(kReduceUserAgentMinorVersion))
+    return UserAgentReductionEnterprisePolicyState::kDefault;
+  switch (pref_service->GetInteger(kReduceUserAgentMinorVersion)) {
+    case 1:
+      return UserAgentReductionEnterprisePolicyState::kForceDisabled;
+    case 2:
+      return UserAgentReductionEnterprisePolicyState::kForceEnabled;
+    case 0:
+    default:
+      return UserAgentReductionEnterprisePolicyState::kDefault;
+  }
+}
+
 }  // namespace embedder_support

components/embedder_support/user_agent_utils.h

@@ -29,6 +29,13 @@ enum class ForceMajorVersionToMinorPosition {
   kForceEnabled = 2,
 };
 
+// TODO(crbug.com/1330890): Remove this enum along with policy.
+enum class UserAgentReductionEnterprisePolicyState {
+  kDefault = 0,
+  kForceDisabled = 1,
+  kForceEnabled = 2,
+};
+
 struct UserAgentOptions {
   bool force_major_version_100 = false;
   ForceMajorVersionToMinorPosition force_major_to_minor =
@@ -43,13 +50,17 @@ struct UserAgentOptions {
 // TODO(crbug.com/1291612): modify to accept an optional PrefService*.
 std::string GetProductAndVersion(
     ForceMajorVersionToMinorPosition force_major_to_minor =
-        ForceMajorVersionToMinorPosition::kDefault);
+        ForceMajorVersionToMinorPosition::kDefault,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction =
+        UserAgentReductionEnterprisePolicyState::kDefault);
 
 // Returns the user agent string for Chrome.
 // TODO(crbug.com/1291612): modify to accept an optional PrefService*.
 std::string GetFullUserAgent(
     ForceMajorVersionToMinorPosition force_major_to_minor =
-        ForceMajorVersionToMinorPosition::kDefault);
+        ForceMajorVersionToMinorPosition::kDefault,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction =
+        UserAgentReductionEnterprisePolicyState::kDefault);
 
 // Returns the reduced user agent string for Chrome.
 // TODO(crbug.com/1291612): modify to accept an optional PrefService*.
@@ -60,8 +71,11 @@ std::string GetReducedUserAgent(
 // Returns the full or "reduced" user agent string, depending on the
 // UserAgentReduction enterprise policy and blink::features::kReduceUserAgent
 // TODO(crbug.com/1291612): modify to accept an optional PrefService*.
-std::string GetUserAgent(ForceMajorVersionToMinorPosition force_major_to_minor =
-                             ForceMajorVersionToMinorPosition::kDefault);
+std::string GetUserAgent(
+    ForceMajorVersionToMinorPosition force_major_to_minor =
+        ForceMajorVersionToMinorPosition::kDefault,
+    UserAgentReductionEnterprisePolicyState user_agent_reduction =
+        UserAgentReductionEnterprisePolicyState::kDefault);
 
 // Returns UserAgentMetadata per the default policy.
 // This override is currently used in fuchsia, where the enterprise policy
@@ -114,6 +128,12 @@ int GetHighestKnownUniversalApiContractVersionForTesting();
 embedder_support::ForceMajorVersionToMinorPosition GetMajorToMinorFromPrefs(
     const PrefService* pref_service);
 
+// Returns the UserAgentReductionEnterprisePolicyState enum value corresponding
+// to the provided integer policy value for UserAgentReduction.
+// TODO(crbug.com/1330890): Remove this function with policy.
+embedder_support::UserAgentReductionEnterprisePolicyState
+GetUserAgentReductionFromPrefs(const PrefService* pref_service);
+
 }  // namespace embedder_support
 
 #endif  // COMPONENTS_EMBEDDER_SUPPORT_USER_AGENT_UTILS_H_