[VPN 2.0] Add GetLastConnectionError API to BraveVpnService (#37008)

Currently, SkusInternalsUI uses a call to the VPN connection manager
to get a last VPN error. This is relevant only to Architecture 1.0,
since in Architecture 2.0 there is no connection manager in the
browser. Hence we need to implement an implementation-agnotic API
in the BraveVpnService, to access the last VPN connection error in
SkusInternalsUI. This change introduces this new API.

Resolves https://github.com/brave/brave-browser/issues/55762

browser/ui/BUILD.gn

@@ -993,7 +993,6 @@ source_set("ui") {
     ]
   }
   if (enable_brave_vpn_v1) {
-    deps += [ "//brave/components/brave_vpn/browser/connection:api" ]
     if (is_win) {
       deps += [
         "//brave/components/brave_vpn/common/win",

browser/ui/webui/skus_internals_ui.cc

@@ -42,10 +42,6 @@
 #include "brave/components/brave_vpn/common/pref_names.h"
 #endif
 
-#if BUILDFLAG(ENABLE_BRAVE_VPN_V1)
-#include "brave/components/brave_vpn/browser/connection/brave_vpn_connection_manager.h"
-#endif
-
 namespace {
 
 void SaveSkusStateToFile(const base::FilePath& path,
@@ -231,10 +227,12 @@ void SkusInternalsUI::FileSelectionCanceled() {
 
 std::string SkusInternalsUI::GetLastVPNConnectionError() const {
   std::string error;
-#if BUILDFLAG(ENABLE_BRAVE_VPN_V1)
-  auto* manager = g_brave_browser_process->brave_vpn_connection_manager();
-  CHECK(manager);
-  error = manager->GetLastConnectionError();
+#if BUILDFLAG(ENABLE_BRAVE_VPN) && !BUILDFLAG(IS_ANDROID)
+  auto* profile = Profile::FromWebUI(web_ui());
+  if (auto* service =
+          brave_vpn::BraveVpnServiceFactory::GetForProfile(profile)) {
+    error = service->GetLastConnectionError();
+  }
 #endif
   return error;
 }

components/brave_vpn/browser/brave_vpn_service.h

@@ -63,6 +63,7 @@ class BraveVpnService : public mojom::ServiceHandler, public KeyedService {
   virtual bool IsConnected() const = 0;
   virtual void ToggleConnection() = 0;
   virtual mojom::ConnectionState GetConnectionState() const = 0;
+  virtual std::string GetLastConnectionError() const = 0;
   virtual void RecordWidgetUsageMetrics(bool new_usage) = 0;
 #else   //  !BUILDFLAG(IS_ANDROID)
   // Public interface for Android native worker.

components/brave_vpn/browser/brave_vpn_service_impl.cc

@@ -122,6 +122,11 @@ std::string BraveVpnServiceImpl::GetCurrentEnvironment() const {
 }
 
 #if !BUILDFLAG(IS_ANDROID)
+std::string BraveVpnServiceImpl::GetLastConnectionError() const {
+  CHECK(connection_manager_);
+  return connection_manager_->GetLastConnectionError();
+}
+
 void BraveVpnServiceImpl::RecordWidgetUsageMetrics(bool new_usage) {
   brave_vpn_metrics_.RecordWidgetUsage(new_usage);
 }

components/brave_vpn/browser/brave_vpn_service_impl.h

@@ -77,6 +77,7 @@ class BraveVpnServiceImpl : public BraveVpnService,
   bool IsConnected() const override;
   void ToggleConnection() override;
   mojom::ConnectionState GetConnectionState() const override;
+  std::string GetLastConnectionError() const override;
   void RecordWidgetUsageMetrics(bool new_usage) override;
 #endif  // !BUILDFLAG(IS_ANDROID)
 

components/brave_vpn/browser/brave_vpn_service_unittest.cc

@@ -45,6 +45,7 @@ class TestBraveVpnService : public BraveVpnService {
   mojom::ConnectionState GetConnectionState() const override {
     return mojom::ConnectionState::DISCONNECTED;
   }
+  std::string GetLastConnectionError() const override { return {}; }
   void RecordWidgetUsageMetrics(bool new_usage) override {}
 #else
   void GetTimezonesForRegions(ResponseCallback callback) override {}

components/brave_vpn/browser/v2/brave_vpn_service_impl.h

@@ -37,6 +37,7 @@ class BraveVpnServiceImpl : public BraveVpnService {
   bool IsConnected() const override;
   void ToggleConnection() override;
   mojom::ConnectionState GetConnectionState() const override;
+  std::string GetLastConnectionError() const override;
   void RecordWidgetUsageMetrics(bool new_usage) override;
 
   // mojom::ServiceHandler overrides:

components/brave_vpn/browser/v2/brave_vpn_service_impl_desktop.cc

@@ -26,6 +26,11 @@ mojom::ConnectionState BraveVpnServiceImpl::GetConnectionState() const {
   return connection_state_;
 }
 
+std::string BraveVpnServiceImpl::GetLastConnectionError() const {
+  NOTIMPLEMENTED();
+  return std::string();
+}
+
 void BraveVpnServiceImpl::RecordWidgetUsageMetrics(bool new_usage) {
   NOTIMPLEMENTED();
 }