Remove GetMetadata from PhysicalWebDataSource and PhysicalWebScanner

ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm

Index: ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm
diff --git a/ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm b/ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm
index 8d56153001109cab8e668c878891a123c76790c3..43247b36404c3a96d9bc2559a35f7f2f395e946b 100644
--- a/ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm
+++ b/ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.mm
@@ -5,7 +5,6 @@
 #import "ios/chrome/browser/physical_web/ios_chrome_physical_web_data_source.h"
 
 #include "base/memory/ptr_util.h"
-#include "base/values.h"
 #import "ios/chrome/browser/physical_web/physical_web_initial_state_recorder.h"
 #import "ios/chrome/common/physical_web/physical_web_scanner.h"
 
@@ -45,13 +44,6 @@ void IOSChromePhysicalWebDataSource::StopDiscovery() {
   scanner_.reset();
 }
 
-std::unique_ptr<base::ListValue> IOSChromePhysicalWebDataSource::GetMetadata() {
-  if (!scanner_) {
-    return base::MakeUnique<base::ListValue>();
-  }
-  return [scanner_ metadata];
-}
-
 std::unique_ptr<physical_web::MetadataList>
 IOSChromePhysicalWebDataSource::GetMetadataList() {
   if (!scanner_) {