Refactor how padding is calculated.

webrtc/modules/pacing/paced_sender_unittest.cc

Index: webrtc/modules/pacing/paced_sender_unittest.cc
diff --git a/webrtc/modules/pacing/paced_sender_unittest.cc b/webrtc/modules/pacing/paced_sender_unittest.cc
index 6a0a006c32600f5bfe0489da183d3957d45b9e34..a80d665585e7a102dc84b196fdf363962cfc7819 100644
--- a/webrtc/modules/pacing/paced_sender_unittest.cc
+++ b/webrtc/modules/pacing/paced_sender_unittest.cc
@@ -357,6 +357,27 @@ TEST_F(PacedSenderTest, Padding) {
   send_bucket_->Process();
 }
 
+TEST_F(PacedSenderTest, NoPaddingBeforeNormalPacket) {
+  send_bucket_->SetEstimatedBitrate(kTargetBitrateBps);
+  send_bucket_->SetAllocatedSendBitrate(kTargetBitrateBps, kTargetBitrateBps);
+
+  EXPECT_CALL(callback_, TimeToSendPadding(_)).Times(0);
+  send_bucket_->Process();
+  clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess());
+
+  send_bucket_->Process();
+  clock_.AdvanceTimeMilliseconds(send_bucket_->TimeUntilNextProcess());
+
+  uint32_t ssrc = 12345;
+  uint16_t sequence_number = 1234;
+  int64_t capture_time_ms = 56789;
+
+  SendAndExpectPacket(PacedSender::kNormalPriority, ssrc, sequence_number++,
+                      capture_time_ms, 250, false);
+  EXPECT_CALL(callback_, TimeToSendPadding(250)).Times(1).WillOnce(Return(250));
+  send_bucket_->Process();
+}
+
 TEST_F(PacedSenderTest, VerifyPaddingUpToBitrate) {
   uint32_t ssrc = 12345;
   uint16_t sequence_number = 1234;
@@ -391,7 +412,10 @@ TEST_F(PacedSenderTest, VerifyAverageBitrateVaryingMediaPayload) {
   send_bucket_.reset(new PacedSender(&clock_, &callback));
   send_bucket_->SetProbingEnabled(false);
   send_bucket_->SetEstimatedBitrate(kTargetBitrateBps);
-  send_bucket_->SetAllocatedSendBitrate(kTargetBitrateBps, kTargetBitrateBps);
+
+  send_bucket_->SetAllocatedSendBitrate(
+      0 /*allocated_bitrate_bps*/,
+      kTargetBitrateBps * 2 /* max_padding_bitrate_bps */);
 
   int64_t start_time = clock_.TimeInMilliseconds();
   size_t media_bytes = 0;