Remove the build id from the Chrome Android user agent for all non-Web View cases.

Per crbug.com/860229, removes the Android build number from the Android user agent, but creates a
Finch experiment that allows the change to be re-enabled.  Does not apply the change to Android
Web View as mandated by the Android Compatibility Definition Document.


Bug: 860229
Cq-Include-Trybots: luci.chromium.try:ios-simulator-full-configs;master.tryserver.chromium.mac:ios-simulator-cronet
Change-Id: I57c24994958d840c80600356f12b2ce20c8a9f74
Reviewed-on: https://chromium-review.googlesource.com/1157225
Commit-Queue: Melissa Galonsky <mgalonsky@chromium.org>
Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Luke Halliwell <halliwell@chromium.org>
Reviewed-by: Nick Harper <nharper@chromium.org>
Reviewed-by: Ryo Hashimoto <hashimoto@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582186}

android_webview/common/aw_content_client.cc

@@ -37,7 +37,8 @@ std::string GetUserAgent() {
         switches::kUseMobileUserAgent)) {
     product += " Mobile";
   }
-  return content::BuildUserAgentFromProductAndExtraOSInfo(product, "; wv");
+  return content::BuildUserAgentFromProductAndExtraOSInfo(
+      product, "; wv", true /* include_android_build_number */);
 }
 
 void AwContentClient::AddAdditionalSchemes(Schemes* schemes) {

chrome/browser/chromeos/drive/drive_integration_service.cc

@@ -101,7 +101,8 @@ std::string GetDriveUserAgent() {
   // This part is <client_name>/<version>.
   const char kLibraryInfo[] = "chrome-cc/none";
 
-  const std::string os_cpu_info = content::BuildOSCpuInfo();
+  const std::string os_cpu_info =
+      content::BuildOSCpuInfo(false /* include_android_build_number */);
 
   // Add "gzip" to receive compressed data from the server.
   // (see https://developers.google.com/drive/performance)

chrome/browser/net/default_network_context_params.cc

@@ -49,7 +49,8 @@ network::mojom::NetworkContextParamsPtr CreateDefaultNetworkContextParams() {
   quic_user_agent_id.append(
       version_info::GetProductNameAndVersionForUserAgent());
   quic_user_agent_id.push_back(' ');
-  quic_user_agent_id.append(content::BuildOSCpuInfo());
+  quic_user_agent_id.append(
+      content::BuildOSCpuInfo(false /* include_android_build_number */));
   network_context_params->quic_user_agent_id = quic_user_agent_id;
 
   const base::CommandLine& command_line =

chromecast/common/cast_content_client.cc

@@ -74,7 +74,7 @@ std::string GetUserAgent() {
       BuildAndroidOsInfo().c_str()
 #else
       "X11; ",
-      content::BuildOSCpuInfo().c_str()
+      content::BuildOSCpuInfo(false /* include_android_build_number */).c_str()
 #endif
       );
   return content::BuildUserAgentFromOSAndProduct(os_info, product) +

content/common/user_agent.cc

@@ -6,6 +6,7 @@
 
 #include <stdint.h>
 
+#include "base/feature_list.h"
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
@@ -21,6 +22,11 @@
 
 namespace content {
 
+#if defined(OS_ANDROID)
+const base::Feature kAndroidUserAgentStringContainsBuildId{
+    "AndroidUserAgentStringContainsBuildId", base::FEATURE_DISABLED_BY_DEFAULT};
+#endif  // defined(OS_ANDROID)
+
 std::string GetWebKitVersion() {
   return base::StringPrintf("%d.%d (%s)",
                             WEBKIT_VERSION_MAJOR,
@@ -32,7 +38,7 @@ std::string GetWebKitRevision() {
   return WEBKIT_SVN_REVISION;
 }
 
-std::string BuildOSCpuInfo() {
+std::string BuildOSCpuInfo(bool include_android_build_number) {
   std::string os_cpu;
 
 #if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_CHROMEOS) ||\
@@ -73,13 +79,17 @@ std::string BuildOSCpuInfo() {
   }
 
   // Append the build ID.
-  std::string android_build_id = base::SysInfo::GetAndroidBuildID();
-  if (android_build_id.size() > 0) {
-    if (!semicolon_inserted) {
-      android_info_str += ";";
+  if (base::FeatureList::IsEnabled(kAndroidUserAgentStringContainsBuildId) ||
+      include_android_build_number) {
+    std::string android_build_id = base::SysInfo::GetAndroidBuildID();
+    if (android_build_id.size() > 0) {
+      if (!semicolon_inserted) {
+        android_info_str += ";";
+      }
+      android_info_str += " Build/" + android_build_id;
     }
-    android_info_str += " Build/" + android_build_id;
   }
+
 #elif (defined(OS_POSIX) && !defined(OS_MACOSX)) || defined(OS_FUCHSIA)
   // Should work on any Posix system.
   struct utsname unixinfo;
@@ -145,26 +155,23 @@ std::string getUserAgentPlatform() {
 
 std::string BuildUserAgentFromProduct(const std::string& product) {
   std::string os_info;
-  base::StringAppendF(
-      &os_info,
-      "%s%s",
-      getUserAgentPlatform().c_str(),
-      BuildOSCpuInfo().c_str());
+  base::StringAppendF(&os_info, "%s%s", getUserAgentPlatform().c_str(),
+                      BuildOSCpuInfo(false).c_str());
   return BuildUserAgentFromOSAndProduct(os_info, product);
 }
 
+#if defined(OS_ANDROID)
 std::string BuildUserAgentFromProductAndExtraOSInfo(
     const std::string& product,
-    const std::string& extra_os_info) {
+    const std::string& extra_os_info,
+    const bool include_android_build_number) {
   std::string os_info;
-  base::StringAppendF(
-      &os_info,
-      "%s%s%s",
-      getUserAgentPlatform().c_str(),
-      BuildOSCpuInfo().c_str(),
-      extra_os_info.c_str());
+  base::StringAppendF(&os_info, "%s%s%s", getUserAgentPlatform().c_str(),
+                      BuildOSCpuInfo(include_android_build_number).c_str(),
+                      extra_os_info.c_str());
   return BuildUserAgentFromOSAndProduct(os_info, product);
 }
+#endif
 
 std::string BuildUserAgentFromOSAndProduct(const std::string& os_info,
                                            const std::string& product) {

content/public/common/user_agent.h

@@ -7,6 +7,7 @@
 
 #include <string>
 
+#include "build/build_config.h"
 #include "content/common/content_export.h"
 
 namespace content {
@@ -17,18 +18,24 @@ CONTENT_EXPORT std::string GetWebKitVersion();
 CONTENT_EXPORT std::string GetWebKitRevision();
 
 // Builds a User-agent compatible string that describes the OS and CPU type.
-CONTENT_EXPORT std::string BuildOSCpuInfo();
+// On Android, the string will only include the build number if true is passed
+// as an argument.
+CONTENT_EXPORT std::string BuildOSCpuInfo(bool include_android_build_number);
 
 // Helper function to generate a full user agent string from a short
 // product name.
 CONTENT_EXPORT std::string BuildUserAgentFromProduct(
     const std::string& product);
 
+#if defined(OS_ANDROID)
 // Helper function to generate a full user agent string given a short
 // product name and some extra text to be added to the OS info.
+// This is currently only used for Android Web View.
 CONTENT_EXPORT std::string BuildUserAgentFromProductAndExtraOSInfo(
-        const std::string& product,
-        const std::string& extra_os_info);
+    const std::string& product,
+    const std::string& extra_os_info,
+    const bool include_android_build_number);
+#endif
 
 // Builds a full user agent string given a string describing the OS and a
 // product name.