sync: Retry soon when server returns conflict

sync/engine/backoff_delay_provider_unittest.cc

Index: sync/engine/backoff_delay_provider_unittest.cc
diff --git a/sync/engine/backoff_delay_provider_unittest.cc b/sync/engine/backoff_delay_provider_unittest.cc
index 8184b0f4ff877b5db17b64bad8b0aaafe5fe8326..4e7bfc211806f554bdd3cb774f3e73208a5981d1 100644
--- a/sync/engine/backoff_delay_provider_unittest.cc
+++ b/sync/engine/backoff_delay_provider_unittest.cc
@@ -72,6 +72,10 @@ TEST_F(BackoffDelayProviderTest, GetInitialDelay) {
   state.commit_result = NETWORK_CONNECTION_UNAVAILABLE;
   EXPECT_EQ(kInitialBackoffImmediateRetrySeconds,
             delay->GetInitialDelay(state).InSeconds());
+
+  state.commit_result = SERVER_RETURN_CONFLICT;
+  EXPECT_EQ(kInitialBackoffImmediateRetrySeconds,
+            delay->GetInitialDelay(state).InSeconds());
 }
 
 TEST_F(BackoffDelayProviderTest, GetInitialDelayWithOverride) {
@@ -106,6 +110,10 @@ TEST_F(BackoffDelayProviderTest, GetInitialDelayWithOverride) {
   state.commit_result = SERVER_RETURN_MIGRATION_DONE;
   EXPECT_EQ(kInitialBackoffImmediateRetrySeconds,
             delay->GetInitialDelay(state).InSeconds());
+
+  state.commit_result = SERVER_RETURN_CONFLICT;
+  EXPECT_EQ(kInitialBackoffImmediateRetrySeconds,
+            delay->GetInitialDelay(state).InSeconds());
 }
 
 }  // namespace syncer