Refactor net::BackoffEntry to not require subclassing

components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
index 7aff4be710b59be0c8858c97d9382c3fd3312793..b3c9c4ac1d27f7d66d159002ec6b2aca863ce568 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
@@ -113,7 +113,7 @@ base::TimeDelta TestDataReductionProxyConfigServiceClient::GetDelay() const {
   return config_refresh_timer_.GetCurrentDelay();
 }
 
-base::Time TestDataReductionProxyConfigServiceClient::Now() const {
+base::Time TestDataReductionProxyConfigServiceClient::Now() {
   return tick_clock_.Now();
 }
 
@@ -128,12 +128,12 @@ TestDataReductionProxyConfigServiceClient::TestTickClock::TestTickClock(
 }
 
 base::TimeTicks
-TestDataReductionProxyConfigServiceClient::TestTickClock::NowTicks() const {
+TestDataReductionProxyConfigServiceClient::TestTickClock::NowTicks() {
   return base::TimeTicks::UnixEpoch() + (time_ - base::Time::UnixEpoch());
 }
 
 base::Time
-TestDataReductionProxyConfigServiceClient::TestTickClock::Now() const {
+TestDataReductionProxyConfigServiceClient::TestTickClock::Now() {
   return time_;
 }
 
@@ -142,19 +142,6 @@ void TestDataReductionProxyConfigServiceClient::TestTickClock::SetTime(
   time_ = time;
 }
 
-TestDataReductionProxyConfigServiceClient::TestBackoffEntry::TestBackoffEntry(
-    const net::BackoffEntry::Policy* const policy,
-    const TestTickClock* tick_clock)
-    : net::BackoffEntry(policy),
-      tick_clock_(tick_clock) {
-}
-
-base::TimeTicks
-TestDataReductionProxyConfigServiceClient::TestBackoffEntry::ImplGetTimeNow()
-    const {
-  return tick_clock_->NowTicks();
-}
-
 MockDataReductionProxyService::MockDataReductionProxyService(
     scoped_ptr<DataReductionProxyCompressionStats> compression_stats,
     DataReductionProxySettings* settings,