Create feature and enable data collection for Data Saver site breakdown

chrome/browser/flag_descriptions.h

Index: chrome/browser/flag_descriptions.h
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 78782b247aaad18eb5e803823456fb62e79e3fca..0a8e92e084a0677aa9e0ffaef6e17229a9965f16 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -1294,6 +1294,14 @@ extern const char kEnableDataReductionProxyMainMenuName[];
 // main menu rather than under settings on Android
 extern const char kEnableDataReductionProxyMainMenuDescription[];
 
+// An about:flags experiment title to enable the site breakdown on the Data
+// Saver settings page.
+extern const char kEnableDataReductionProxySiteBreakdownName[];
+
+// Describes an about:flags experiment to enable the site breakdown on the Data
+// Saver settings page.
+extern const char kEnableDataReductionProxySiteBreakdownDescription[];
+
 #endif  // defined(OS_ANDROID)
 
 // Name of about:flags option for LCD text.