Associate a scan mode with Physical Web listeners

components/physical_web/data_source/physical_web_data_source_impl.cc

Index: components/physical_web/data_source/physical_web_data_source_impl.cc
diff --git a/components/physical_web/data_source/physical_web_data_source_impl.cc b/components/physical_web/data_source/physical_web_data_source_impl.cc
index 86b4c185a14c34328c6e4c36de6b023f0730e925..222cb3a4de16c0ed2c35d7bccba3311045543da0 100644
--- a/components/physical_web/data_source/physical_web_data_source_impl.cc
+++ b/components/physical_web/data_source/physical_web_data_source_impl.cc
@@ -14,13 +14,15 @@ PhysicalWebDataSourceImpl::PhysicalWebDataSourceImpl() {}
 PhysicalWebDataSourceImpl::~PhysicalWebDataSourceImpl() {}
 
 void PhysicalWebDataSourceImpl::RegisterListener(
-    PhysicalWebListener* physical_web_listener) {
+    PhysicalWebListener* physical_web_listener, ScanMode scan_mode) {
   observer_list_.AddObserver(physical_web_listener);

[mattreynolds, 2017/03/21 19:02:56]

ObserverList says observers shouldn't be added more than once. Can you add a
check here to ensure we won't double-add when changing the scan mode?

[cco3, 2017/03/21 19:28:45]

O snap.

+  scan_modes_[physical_web_listener] = scan_mode;
 }
 
 void PhysicalWebDataSourceImpl::UnregisterListener(
     PhysicalWebListener* physical_web_listener) {
   observer_list_.RemoveObserver(physical_web_listener);
+  scan_modes_.erase(scan_modes_.find(physical_web_listener));
 }
 
 void PhysicalWebDataSourceImpl::NotifyOnFound(const GURL& url) {