Add support for command line switches to Features, and as proof that it works,

extensions/common/features/simple_feature_unittest.cc

Index: extensions/common/features/simple_feature_unittest.cc
diff --git a/extensions/common/features/simple_feature_unittest.cc b/extensions/common/features/simple_feature_unittest.cc
index 40e1e2a6cfaa684b7b1608508dde9f6462fd7203..9f723fab0663d23e8a49bad83c792fcf0e0039f1 100644
--- a/extensions/common/features/simple_feature_unittest.cc
+++ b/extensions/common/features/simple_feature_unittest.cc
@@ -6,6 +6,7 @@
 
 #include <string>
 
+#include "base/command_line.h"
 #include "base/values.h"
 #include "extensions/common/manifest.h"
 #include "extensions/common/value_builder.h"
@@ -37,6 +38,21 @@ bool LocationIsAvailable(SimpleFeature::Location feature_location,
   return availability_result == Feature::IS_AVAILABLE;
 }
 
+class ScopedCommandLineSwitch {
+ public:
+  explicit ScopedCommandLineSwitch(const std::string& arg)
+      : original_command_line_(*base::CommandLine::ForCurrentProcess()) {
+    base::CommandLine::ForCurrentProcess()->AppendSwitch(arg);
+  }
+
+  ~ScopedCommandLineSwitch() {
+    *base::CommandLine::ForCurrentProcess() = original_command_line_;
+  }
+
+ private:
+  base::CommandLine original_command_line_;
+};
+
 }  // namespace
 
 TEST(SimpleFeatureTest, IsAvailableNullCase) {
@@ -649,4 +665,38 @@ TEST(SimpleFeatureTest, Inheritance) {
   EXPECT_EQ(3, feature.max_manifest_version());
 }
 
+TEST(SimpleFeatureTest, CommandLineSwitch) {
+  SimpleFeature feature;
+  feature.set_command_line_switch("laser-beams");
+  {
+    EXPECT_EQ(Feature::MISSING_COMMAND_LINE_SWITCH,
+              feature.IsAvailableToEnvironment().result());
+  }
+  {
+    ScopedCommandLineSwitch scoped_switch("laser-beams");
+    EXPECT_EQ(Feature::MISSING_COMMAND_LINE_SWITCH,
+              feature.IsAvailableToEnvironment().result());
+  }
+  {
+    ScopedCommandLineSwitch scoped_switch("enable-laser-beams");
+    EXPECT_EQ(Feature::IS_AVAILABLE,
+              feature.IsAvailableToEnvironment().result());
+  }
+  {
+    ScopedCommandLineSwitch scoped_switch("disable-laser-beams");
+    EXPECT_EQ(Feature::MISSING_COMMAND_LINE_SWITCH,
+              feature.IsAvailableToEnvironment().result());
+  }
+  {
+    ScopedCommandLineSwitch scoped_switch("laser-beams=1");
+    EXPECT_EQ(Feature::IS_AVAILABLE,
+              feature.IsAvailableToEnvironment().result());
+  }
+  {
+    ScopedCommandLineSwitch scoped_switch("laser-beams=0");
+    EXPECT_EQ(Feature::MISSING_COMMAND_LINE_SWITCH,
+              feature.IsAvailableToEnvironment().result());
+  }
+}
+
 }  // namespace extensions