Run software reporter's experimental engine on all architectures

chrome/browser/component_updater/sw_reporter_installer_win.cc

Index: chrome/browser/component_updater/sw_reporter_installer_win.cc
diff --git a/chrome/browser/component_updater/sw_reporter_installer_win.cc b/chrome/browser/component_updater/sw_reporter_installer_win.cc
index 8d28b344176f8a2deac9ebd0ae86444024faf79f..c558cfd468619d0e494ba6701a371b3b5ff807cb 100644
--- a/chrome/browser/component_updater/sw_reporter_installer_win.cc
+++ b/chrome/browser/component_updater/sw_reporter_installer_win.cc
@@ -83,6 +83,10 @@ const wchar_t kVersionValueName[] = L"Version";
 
 constexpr base::Feature kExperimentalEngineFeature{
     "ExperimentalSwReporterEngine", base::FEATURE_DISABLED_BY_DEFAULT};
+constexpr base::Feature kExperimentalEngineAllArchsFeature{
+    "ExperimentalSwReporterEngineOnAllArchitectures",
+    base::FEATURE_DISABLED_BY_DEFAULT
+};
 
 void SRTHasCompleted(SRTCompleted value) {
   UMA_HISTOGRAM_ENUMERATION("SoftwareReporter.Cleaner.HasCompleted", value,
@@ -475,11 +479,15 @@ void RegisterSwReporterComponent(ComponentUpdateService* cus) {
     }
   }
 
-  // The experiment is only enabled on x86. There's no way to check this in the
+  // If the experiment is not explicitly enabled on all platforms, it
+  // should be only enabled on x86. There's no way to check this in the
   // variations config so we'll hard-code it.
-  const bool is_experimental_engine_supported =
+  const bool is_x86_architecture =
       base::win::OSInfo::GetInstance()->architecture() ==
       base::win::OSInfo::X86_ARCHITECTURE;
+  const bool is_experimental_engine_supported =
+      base::FeatureList::IsEnabled(kExperimentalEngineAllArchsFeature) ||
+      is_x86_architecture;

[Joe Mason, 2017/01/24 21:06:14]

Nit: I don't think the extra "is_x86_architecture" variable name adds any
clarity here. I'd just use ||.

[veranika, 2017/01/25 16:12:59]

Acknowledged.
I agree that it isn't necessary, but because of the variable length the inlined
expression is harder to understand, and using parenthesis would be ugly:

base::FeatureList::IsEnabled(kExperimentalEngineAllArchsFeature) ||
base::win::OSInfo::GetInstance()->architecture() ==
base::win::OSInfo::X86_ARCHITECTURE;

[joenotcharles, 2017/01/25 16:19:29]

Acknowledged.

 
   // Install the component.
   std::unique_ptr<ComponentInstallerTraits> traits(