[CrOS Tether] Create BleScanner, a class which scan BLE advertisements and identifies nearby device…

components/cryptauth/mock_eid_generator.cc

Index: components/cryptauth/mock_eid_generator.cc
diff --git a/components/cryptauth/mock_eid_generator.cc b/components/cryptauth/mock_eid_generator.cc
index adebf26b78e89fe1f7594fe5e5aa6c7bc92a8772..c9515a74086aa7b70c71c155dc9bbee338c1f8e4 100644
--- a/components/cryptauth/mock_eid_generator.cc
+++ b/components/cryptauth/mock_eid_generator.cc
@@ -11,7 +11,8 @@ namespace cryptauth {
 MockEidGenerator::MockEidGenerator() : background_scan_filter_(nullptr),
                                        advertisement_(nullptr),
                                        possible_advertisements_(nullptr),
-                                       identified_device_(nullptr) {}
+                                       identified_device_(nullptr),
+                                       num_identify_calls_(0) {}
 
 MockEidGenerator::~MockEidGenerator() {}
 
@@ -62,6 +63,11 @@ RemoteDevice const* MockEidGenerator::IdentifyRemoteDeviceByAdvertisement(
     const std::string& advertisement_service_data,
     const std::vector<RemoteDevice>& device_list,
     const std::vector<BeaconSeed>& scanning_device_beacon_seeds) const {
+  // Increment num_identify_calls_. Since this overrides a const method, some
+  // hacking is needed to modify the num_identify_calls_ instance variable.
+  int* num_identify_calls_ptr = const_cast<int*>(&num_identify_calls_);
+  *num_identify_calls_ptr = *num_identify_calls_ptr + 1;
+
   return identified_device_;
 }