sync: add InternalComponentsFactory::Switches to simplify passing switches to internal components.

sync/engine/sync_scheduler_impl.cc

Index: sync/engine/sync_scheduler_impl.cc
diff --git a/sync/engine/sync_scheduler_impl.cc b/sync/engine/sync_scheduler_impl.cc
index 6db3260fd93539794f0be2b16e8135d1c8133186..ff177b4f8347ec1bcd5582ee5c4873bb1cf948ec 100644
--- a/sync/engine/sync_scheduler_impl.cc
+++ b/sync/engine/sync_scheduler_impl.cc
@@ -12,7 +12,7 @@
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/rand_util.h"
+#include "sync/engine/backoff_delay_provider.h"
 #include "sync/engine/syncer.h"
 #include "sync/engine/throttled_data_type_tracker.h"
 #include "sync/protocol/proto_enum_conversions.h"
@@ -32,11 +32,6 @@ using sync_pb::GetUpdatesCallerInfo;
 
 namespace {
 
-// For integration tests only.  Override initial backoff value.
-// TODO(tim): Remove this egregiousness, use command line flag and plumb
-// through. Done this way to reduce diffs in hotfix.
-static bool g_force_short_retry = false;
-
 bool ShouldRequestEarlyExit(const SyncProtocolError& error) {
   switch (error.error_type) {
     case SYNC_SUCCESS:
@@ -85,9 +80,6 @@ ConfigurationParams::ConfigurationParams(
 }
 ConfigurationParams::~ConfigurationParams() {}
 
-SyncSchedulerImpl::DelayProvider::DelayProvider() {}
-SyncSchedulerImpl::DelayProvider::~DelayProvider() {}
-
 SyncSchedulerImpl::WaitInterval::WaitInterval()
     : mode(UNKNOWN),
       had_nudge(false) {
@@ -140,11 +132,6 @@ const char* SyncSchedulerImpl::SyncSessionJob::GetPurposeString(
   return "";
 }
 
-TimeDelta SyncSchedulerImpl::DelayProvider::GetDelay(
-    const base::TimeDelta& last_delay) {
-  return SyncSchedulerImpl::GetRecommendedDelay(last_delay);
-}
-
 GetUpdatesCallerInfo::GetUpdatesSource GetUpdatesFromNudgeSource(
     NudgeSource source) {
   switch (source) {
@@ -197,6 +184,7 @@ bool IsConfigRelatedUpdateSourceValue(
 }  // namespace
 
 SyncSchedulerImpl::SyncSchedulerImpl(const std::string& name,
+                                     BackoffDelayProvider* delay_provider,
                                      sessions::SyncSessionContext* context,
                                      Syncer* syncer)
     : weak_ptr_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
@@ -216,7 +204,7 @@ SyncSchedulerImpl::SyncSchedulerImpl(const std::string& name,
       // Start with assuming everything is fine with the connection.
       // At the end of the sync cycle we would have the correct status.
       connection_code_(HttpResponse::SERVER_CONNECTION_OK),
-      delay_provider_(new DelayProvider()),
+      delay_provider_(delay_provider),
       syncer_(syncer),
       session_context_(context) {
   DCHECK(sync_loop_);
@@ -903,43 +891,6 @@ void SyncSchedulerImpl::RestartWaiting() {
                               this, &SyncSchedulerImpl::DoCanaryJob);
 }
 
-namespace {
-// TODO(tim): Move this function to syncer_error.h.
-// Return true if the command in question was attempted and did not complete
-// successfully.
-bool IsError(SyncerError error) {
-  return error != UNSET && error != SYNCER_OK;
-}
-}  // namespace
-
-// static
-void SyncSchedulerImpl::ForceShortInitialBackoffRetry() {
-  g_force_short_retry = true;
-}
-
-TimeDelta SyncSchedulerImpl::GetInitialBackoffDelay(
-    const sessions::ModelNeutralState& state) const {
-  // TODO(tim): Remove this, provide integration-test-only mechanism
-  // for override.
-  if (g_force_short_retry) {
-    return TimeDelta::FromSeconds(kInitialBackoffShortRetrySeconds);
-  }
-
-  if (IsError(state.last_get_key_result))
-    return TimeDelta::FromSeconds(kInitialBackoffRetrySeconds);
-  // Note: If we received a MIGRATION_DONE on download updates, then commit
-  // should not have taken place.  Moreover, if we receive a MIGRATION_DONE
-  // on commit, it means that download updates succeeded.  Therefore, we only
-  // need to check if either code is equal to SERVER_RETURN_MIGRATION_DONE,
-  // and not if there were any more serious errors requiring the long retry.
-  if (state.last_download_updates_result == SERVER_RETURN_MIGRATION_DONE ||
-      state.commit_result == SERVER_RETURN_MIGRATION_DONE) {
-    return TimeDelta::FromSeconds(kInitialBackoffShortRetrySeconds);
-  }
-
-  return TimeDelta::FromSeconds(kInitialBackoffRetrySeconds);
-}
-
 void SyncSchedulerImpl::HandleContinuationError(
     const SyncSessionJob& old_job) {
   DCHECK_EQ(MessageLoop::current(), sync_loop_);
@@ -951,7 +902,7 @@ void SyncSchedulerImpl::HandleContinuationError(
 
   TimeDelta length = delay_provider_->GetDelay(
       IsBackingOff() ? wait_interval_->length :
-          GetInitialBackoffDelay(
+          delay_provider_->GetInitialDelay(
               old_job.session->status_controller().model_neutral_state()));
 
   SDVLOG(2) << "In handle continuation error with "
@@ -984,30 +935,6 @@ void SyncSchedulerImpl::HandleContinuationError(
   RestartWaiting();
 }
 
-// static
-TimeDelta SyncSchedulerImpl::GetRecommendedDelay(const TimeDelta& last_delay) {
-  if (last_delay.InSeconds() >= kMaxBackoffSeconds)
-    return TimeDelta::FromSeconds(kMaxBackoffSeconds);
-
-  // This calculates approx. base_delay_seconds * 2 +/- base_delay_seconds / 2
-  int64 backoff_s =
-      std::max(static_cast<int64>(1),
-               last_delay.InSeconds() * kBackoffRandomizationFactor);
-
-  // Flip a coin to randomize backoff interval by +/- 50%.
-  int rand_sign = base::RandInt(0, 1) * 2 - 1;
-
-  // Truncation is adequate for rounding here.
-  backoff_s = backoff_s +
-      (rand_sign * (last_delay.InSeconds() / kBackoffRandomizationFactor));
-
-  // Cap the backoff interval.
-  backoff_s = std::max(static_cast<int64>(1),
-                       std::min(backoff_s, kMaxBackoffSeconds));
-
-  return TimeDelta::FromSeconds(backoff_s);
-}
-
 void SyncSchedulerImpl::RequestStop(const base::Closure& callback) {
   syncer_->RequestEarlyExit();  // Safe to call from any thread.
   DCHECK(weak_handle_this_.IsInitialized());