Implements an UpdateClient::SendUninstallPing API for the

components/component_updater/component_updater_service_unittest.cc

Index: components/component_updater/component_updater_service_unittest.cc
diff --git a/components/component_updater/component_updater_service_unittest.cc b/components/component_updater/component_updater_service_unittest.cc
index a5a839d894d3169bcd5c88f9aa7e8ccdf7a324bc..15b62bb853b087008a9839e768f104ac969ce3d9 100644
--- a/components/component_updater/component_updater_service_unittest.cc
+++ b/components/component_updater/component_updater_service_unittest.cc
@@ -72,6 +72,8 @@ class MockUpdateClient : public UpdateClient {
                      bool(const std::string& id, CrxUpdateItem* update_item));
   MOCK_CONST_METHOD1(IsUpdating, bool(const std::string& id));
   MOCK_METHOD0(Stop, void());
+  MOCK_METHOD3(SendUninstallPing,
+               void(const std::string& id, const Version& version, int reason));
 
  private:
   ~MockUpdateClient() override;