address comments and fix clang tidy tests that failed: replace initia…

…l delay argument string with minimum delay, remove error handling, and update tests with new backoff strategy limits

google/cloud/internal/backoff_policy.h

@@ -181,8 +181,8 @@ class ExponentialBackoffPolicy : public BackoffPolicy {
   template <typename Rep1, typename Period1, typename Rep2, typename Period2,
             typename Rep3, typename Period3>
   ExponentialBackoffPolicy(
-      std::chrono::duration<Rep1, Period1> initial_delay_range,
-      std::chrono::duration<Rep2, Period2> minimum_delay,
+      std::chrono::duration<Rep1, Period1> minimum_delay,
+      std::chrono::duration<Rep2, Period2> initial_delay_upper_bound,
       std::chrono::duration<Rep3, Period3> maximum_delay, double scaling)
       : minimum_delay_(minimum_delay),
         initial_delay_upper_bound_(initial_delay_upper_bound),

google/cloud/internal/backoff_policy_test.cc

@@ -43,42 +43,6 @@ TEST(ExponentialBackoffPolicy, Simple) {
 TEST(ExponentialBackoffPolicy, VerifyFullJitterPolicy) {
   ExponentialBackoffPolicy tested(ms(0), ms(10), ms(50), 2.0);
 
-  auto delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(10), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(20), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(40), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(10), delay);
-  EXPECT_GE(ms(100), delay);
-}
-
-/// @test Verify a full jitter policy, where the minimum delay is set to 0.
-TEST(ExponentialBackoffPolicy, VerifyFullJitterPolicy) {
-  ExponentialBackoffPolicy tested(ms(0), ms(10), ms(50), 2.0);
-
-  auto delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(10), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(20), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(0), delay);
-  EXPECT_GE(ms(40), delay);
-  delay = tested.OnCompletion();
-  EXPECT_LE(ms(10), delay);
-  EXPECT_GE(ms(100), delay);
-}
-
-/// @test Verify a full jitter policy, where the minimum delay is set to 0.
-TEST(ExponentialBackoffPolicy, VerifyFullJitterPolicy) {
-  ExponentialBackoffPolicy tested(ms(10), ms(0), ms(50), 2.0);
-
   auto delay = tested.OnCompletion();
   EXPECT_LE(ms(0), delay);
   EXPECT_GE(ms(10), delay);