PVer4: Test checksum on startup outside the hotpath of DB load

components/safe_browsing_db/v4_store_unittest.cc

Index: components/safe_browsing_db/v4_store_unittest.cc
diff --git a/components/safe_browsing_db/v4_store_unittest.cc b/components/safe_browsing_db/v4_store_unittest.cc
index 90c6525fa88ca316d0051a6fabf0e73147e51e6f..108f188dd17f80577a87c2fc4b09b4018f0f71f9 100644
--- a/components/safe_browsing_db/v4_store_unittest.cc
+++ b/components/safe_browsing_db/v4_store_unittest.cc
@@ -800,4 +800,22 @@ TEST_F(V4StoreTest, TestMergeUpdatesFailsChecksum) {
                 .MergeUpdate(prefix_map_old, HashPrefixMap(), nullptr, "aawc"));
 }
 
+TEST_F(V4StoreTest, TestChecksumErrorOnStartup) {
+  ListUpdateResponse list_update_response;
+  list_update_response.set_new_client_state("test_client_state");
+  list_update_response.set_platform_type(LINUX_PLATFORM);
+  list_update_response.set_response_type(ListUpdateResponse::FULL_UPDATE);
+  list_update_response.mutable_checksum()->set_sha256("checksum");
+  WriteFileFormatProtoToFile(0x600D71FE, 9, &list_update_response);
+  V4Store store(task_runner_, store_path_);
+  EXPECT_TRUE(store.expected_checksum_.empty());
+
+  EXPECT_EQ(READ_SUCCESS, store.ReadFromDisk());
+  EXPECT_TRUE(!store.expected_checksum_.empty());
+  EXPECT_EQ("test_client_state", store.state());
+
+  EXPECT_FALSE(store.VerifyChecksum());
+  // The database schedules the checksum verification.
+}
+
 }  // namespace safe_browsing