[rtp_rtcp] lint errors about rand() usage fixed.

webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc b/webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc
index 541f522f8d1e44ce9d148d7d6bf1000b7db1f21f..80f961bd1eb99876c3879e8ed70195830bee9eaf 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_fec_unittest.cc
@@ -11,6 +11,7 @@
 #include <list>
 
 #include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/base/random.h"
 #include "webrtc/modules/rtp_rtcp/source/byte_io.h"
 #include "webrtc/modules/rtp_rtcp/source/forward_error_correction.h"
 
@@ -41,8 +42,12 @@ template <typename T> void ClearList(std::list<T*>* my_list) {
 class RtpFecTest : public ::testing::Test {
  protected:
   RtpFecTest()
-      : fec_(new ForwardErrorCorrection()), ssrc_(rand()), fec_seq_num_(0) {}
+      : random_(0xfec133700742),
+        fec_(new ForwardErrorCorrection()),
+        ssrc_(random_.Rand<uint32_t>()),
+        fec_seq_num_(0) {}
 
+  webrtc::Random random_;
   ForwardErrorCorrection* fec_;
   int ssrc_;
   uint16_t fec_seq_num_;
@@ -891,22 +896,20 @@ int RtpFecTest::ConstructMediaPacketsSeqNum(int num_media_packets,
   assert(num_media_packets > 0);
   ForwardErrorCorrection::Packet* media_packet = NULL;
   int sequence_number = start_seq_num;
-  int time_stamp = rand();
+  int time_stamp = random_.Rand<int>();
 
   for (int i = 0; i < num_media_packets; ++i) {
     media_packet = new ForwardErrorCorrection::Packet;
     media_packet_list_.push_back(media_packet);
-    media_packet->length = static_cast<size_t>(
-        (static_cast<float>(rand()) / RAND_MAX) *
-        (IP_PACKET_SIZE - kRtpHeaderSize - kTransportOverhead -
-         ForwardErrorCorrection::PacketOverhead()));
+    const uint32_t kMinPacketSize = kRtpHeaderSize;
+    const uint32_t kMaxPacketSize = IP_PACKET_SIZE - kRtpHeaderSize -
+                                    kTransportOverhead -
+                                    ForwardErrorCorrection::PacketOverhead();
+    media_packet->length = random_.Rand(kMinPacketSize, kMaxPacketSize);
 
-    if (media_packet->length < kRtpHeaderSize) {
-      media_packet->length = kRtpHeaderSize;
-    }
     // Generate random values for the first 2 bytes
-    media_packet->data[0] = static_cast<uint8_t>(rand() % 256);
-    media_packet->data[1] = static_cast<uint8_t>(rand() % 256);
+    media_packet->data[0] = random_.Rand<uint8_t>();
+    media_packet->data[1] = random_.Rand<uint8_t>();
 
     // The first two bits are assumed to be 10 by the FEC encoder.
     // In fact the FEC decoder will set the two first bits to 10 regardless of
@@ -929,7 +932,7 @@ int RtpFecTest::ConstructMediaPacketsSeqNum(int num_media_packets,
 
     // Generate random values for payload.
     for (size_t j = 12; j < media_packet->length; ++j) {
-      media_packet->data[j] = static_cast<uint8_t>(rand() % 256);
+      media_packet->data[j] = random_.Rand<uint8_t>();
     }
     sequence_number++;
   }
@@ -940,5 +943,5 @@ int RtpFecTest::ConstructMediaPacketsSeqNum(int num_media_packets,
 }
 
 int RtpFecTest::ConstructMediaPackets(int num_media_packets) {
-  return ConstructMediaPacketsSeqNum(num_media_packets, rand());
+  return ConstructMediaPacketsSeqNum(num_media_packets, random_.Rand<int>());
 }