[sync] Check against nullptr web_data_backend->GetDatabase()

components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc

Index: components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc
diff --git a/components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc b/components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc
index 668ff4165a654fab97ae92d464a1d407b3fc05b7..59506b1c911a8e2cadddfd2f030e6b0e0de77deb 100644
--- a/components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc
+++ b/components/autofill/core/browser/webdata/autocomplete_sync_bridge_unittest.cc
@@ -141,10 +141,10 @@ class AutocompleteSyncBridgeTest : public testing::Test {
   }
   ~AutocompleteSyncBridgeTest() override {}
 
-  void ResetBridge() {
+  void ResetBridge(bool expect_error = false) {
     bridge_.reset(new AutocompleteSyncBridge(
-        &backend_,
-        RecordingModelTypeChangeProcessor::FactoryForBridgeTest(&processor_)));
+        &backend_, RecordingModelTypeChangeProcessor::FactoryForBridgeTest(
+                       &processor_, expect_error)));
   }
 
   void SaveSpecificsToTable(
@@ -266,6 +266,8 @@ class AutocompleteSyncBridgeTest : public testing::Test {
 
   AutofillTable* table() { return &table_; }
 
+  FakeAutofillBackend* backend() { return &backend_; }
+
  private:
   ScopedTempDir temp_dir_;
   base::test::ScopedTaskEnvironment scoped_task_environment_;
@@ -592,6 +594,12 @@ TEST_F(AutocompleteSyncBridgeTest, LoadMetadataCalled) {
   EXPECT_EQ(1u, processor().metadata()->TakeAllMetadata().size());
 }
 
+TEST_F(AutocompleteSyncBridgeTest, LoadMetadataReportsErrorForMissingDB) {
+  backend()->SetWebDatabase(nullptr);
+  // The processor's destructor will verify that an error has occured.
+  ResetBridge(/*expect_error=*/true);
+}
+
 TEST_F(AutocompleteSyncBridgeTest, MergeSyncDataEmpty) {
   VerifyMerge(std::vector<AutofillSpecifics>());