Fix foregound vs background data use measurement

components/data_use_measurement/core/data_use_user_data.h

Index: components/data_use_measurement/core/data_use_user_data.h
diff --git a/components/data_use_measurement/core/data_use_user_data.h b/components/data_use_measurement/core/data_use_user_data.h
index 00d749c2a217db14dcb9210fc100afd8cc2ae75b..579bf1d708d82c9d6847503feb66c0099434e6d3 100644
--- a/components/data_use_measurement/core/data_use_user_data.h
+++ b/components/data_use_measurement/core/data_use_user_data.h
@@ -42,7 +42,11 @@ class DataUseUserData : public base::SupportsUserData::Data {
     NTP_SNIPPETS,
   };
 
-  explicit DataUseUserData(ServiceName service_name);
+  // The state of the application. Only available on Android and on other
+  // platforms it is always FOREGROUND.
+  enum AppState { UNKNOWN, BACKGROUND, FOREGROUND };
+
+  DataUseUserData(ServiceName service_name, AppState app_state);
   ~DataUseUserData() override;
 
   // Helper function to create DataUseUserData. The caller takes the ownership
@@ -60,12 +64,17 @@ class DataUseUserData : public base::SupportsUserData::Data {
 
   ServiceName service_name() const { return service_name_; }
 
+  AppState app_state() const { return app_state_; }
+
   // The key for retrieving back this type of user data.
   static const void* const kUserDataKey;
 
  private:
   const ServiceName service_name_;
 
+  // App state when the request started.
+  const AppState app_state_;
+
   DISALLOW_COPY_AND_ASSIGN(DataUseUserData);
 };