Change sync conflict resolution for extensions

chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc

Index: chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc
diff --git a/chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc b/chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc
index a5cda2282a38829284cb1b8dedc8562d06fd7610..efb7788a2b6228dd156d84e53ea389dc8309509c 100644
--- a/chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc
+++ b/chrome/browser/sync/test/integration/single_client_extensions_sync_test.cc
@@ -3,13 +3,18 @@
 // found in the LICENSE file.
 
 #include "base/macros.h"
+#include "chrome/browser/sync/test/integration/await_match_status_change_checker.h"
 #include "chrome/browser/sync/test/integration/extensions_helper.h"
 #include "chrome/browser/sync/test/integration/sync_integration_test_util.h"
 #include "chrome/browser/sync/test/integration/sync_test.h"
 #include "components/browser_sync/browser/profile_sync_service.h"
+#include "sync/test/fake_server/tombstone_entity.h"
 
 using extensions_helper::AllProfilesHaveSameExtensionsAsVerifier;
+using extensions_helper::DisableExtension;
+using extensions_helper::GetInstalledExtensions;
 using extensions_helper::InstallExtension;
+using extensions_helper::InstallExtensionForAllProfiles;
 using sync_integration_test_util::AwaitCommitActivityCompletion;
 
 class SingleClientExtensionsSyncTest : public SyncTest {
@@ -56,3 +61,48 @@ IN_PROC_BROWSER_TEST_F(SingleClientExtensionsSyncTest, InstallSomeExtensions) {
 
   ASSERT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
 }
+
+// Helper function for waiting to see the extension count in a profile
+// become a specific number.
+static bool ExtensionCountCheck(Profile* profile, size_t expected_count) {
+  return GetInstalledExtensions(profile).size() == expected_count;
+}
+
+// Tests the case of an uninstall from the server conflicting with a local
+// modification, which we expect to be resolved in favor of the uninstall.
+IN_PROC_BROWSER_TEST_F(SingleClientExtensionsSyncTest, UninstallWinsConflicts) {
+  ASSERT_TRUE(SetupClients());
+
+  // Start with an extension installed, and setup sync.
+  InstallExtensionForAllProfiles(0);
+  ASSERT_TRUE(SetupSync());
+  EXPECT_TRUE(AllProfilesHaveSameExtensionsAsVerifier());
+
+  // Simulate a delete at the server.
+  std::vector<sync_pb::SyncEntity> server_extensions =
+      GetFakeServer()->GetSyncEntitiesByModelType(syncer::EXTENSIONS);
+  ASSERT_EQ(1ul, server_extensions.size());
+  std::string entity_id = server_extensions[0].id_string();
+  scoped_ptr<fake_server::FakeServerEntity> tombstone(
+      fake_server::TombstoneEntity::Create(entity_id));
+  GetFakeServer()->InjectEntity(std::move(tombstone));
+
+  // Modify the extension in the local profile to cause a conflict.
+  DisableExtension(GetProfile(0), 0);
+  EXPECT_EQ(1u, GetInstalledExtensions(GetProfile(0)).size());
+
+  // Trigger sync, and expect the extension to remain uninstalled at the server
+  // and get uninstalled locally.
+  const syncer::ModelTypeSet kExtensionsType(syncer::EXTENSIONS);
+  TriggerSyncForModelTypes(0, kExtensionsType);
+  server_extensions =
+      GetFakeServer()->GetSyncEntitiesByModelType(syncer::EXTENSIONS);
+  EXPECT_EQ(0ul, server_extensions.size());
+
+  AwaitMatchStatusChangeChecker checker(
+      base::Bind(&ExtensionCountCheck, GetProfile(0), 0u),
+      "Waiting for profile to have no extensions");
+  checker.Wait();
+  EXPECT_TRUE(!checker.TimedOut());
+  EXPECT_TRUE(GetInstalledExtensions(GetProfile(0)).empty());
+}