[Media Router] Remove MR FeatureSwitch's dependency on EAR.

extensions/common/feature_switch.h

Index: extensions/common/feature_switch.h
diff --git a/extensions/common/feature_switch.h b/extensions/common/feature_switch.h
index b39cc8c3cf0825ab1cb7a5a40c308f6bef7f83bb..c170f9c2fb8f91cd74ef99130fc9630d3d1492e0 100644
--- a/extensions/common/feature_switch.h
+++ b/extensions/common/feature_switch.h
@@ -6,7 +6,6 @@
 #define EXTENSIONS_COMMON_FEATURE_SWITCH_H_
 
 #include <string>
-#include <vector>
 
 #include "base/macros.h"
 
@@ -27,10 +26,8 @@ namespace extensions {
 //    the finch config).
 // 3. If there is a switch name, and the switch is present in the command line,
 //    the command line value will be used.
-// 4. If there are field trials associated with the feature, and the machine
-//    is in the "Enabled" group for all field trials, then the feature is
-//    enabled. If the machine is in the "Disabled" group for any field trials,
-//    the feature is disabled.
+// 4. If there is a finch experiment associated and applicable to the machine,
+//    the finch value will be used.
 // 5. Otherwise, the default value is used.
 class FeatureSwitch {
  public:
@@ -75,17 +72,13 @@ class FeatureSwitch {
   FeatureSwitch(const char* switch_name,
                 const char* field_trial_name,
                 DefaultValue default_value);
-  FeatureSwitch(const char* switch_name,
-                const std::vector<std::string>& required_field_trials,
-                DefaultValue default_value);
   FeatureSwitch(const base::CommandLine* command_line,
                 const char* switch_name,
                 DefaultValue default_value);
   FeatureSwitch(const base::CommandLine* command_line,
                 const char* switch_name,
-                const std::vector<std::string>& required_field_trials,
+                const char* field_trial_name,
                 DefaultValue default_value);
-  ~FeatureSwitch();
 
   // Consider using ScopedOverride instead.
   void SetOverrideValue(OverrideValue value);
@@ -99,7 +92,7 @@ class FeatureSwitch {
 
   const base::CommandLine* command_line_;
   const char* switch_name_;
-  std::vector<std::string> required_field_trials_;
+  const char* field_trial_name_;
   bool default_value_;
   OverrideValue override_value_;