Use size_t more consistently for packet/payload lengths.

See design doc at https://docs.google.com/a/chromium.org/document/d/1I6nmE9D_BmCY-IoV6MDPY2V6WYpEI-dg2apWXTfZyUI/edit?usp=sharing for more information.

This CL was reviewed and approved in pieces in the following CLs:
https://webrtc-codereview.appspot.com/24209004/
https://webrtc-codereview.appspot.com/24229004/
https://webrtc-codereview.appspot.com/24259004/
https://webrtc-codereview.appspot.com/25109004/
https://webrtc-codereview.appspot.com/26099004/
https://webrtc-codereview.appspot.com/27069004/
https://webrtc-codereview.appspot.com/27969004/
https://webrtc-codereview.appspot.com/27989004/
https://webrtc-codereview.appspot.com/29009004/
https://webrtc-codereview.appspot.com/30929004/
https://webrtc-codereview.appspot.com/30939004/
https://webrtc-codereview.appspot.com/31999004/
Committing as TBR to the original reviewers.

BUG=chromium:81439
TEST=none
TBR=pthatcher,henrik.lundin,tina.legrand,stefan,tkchin,glaznev,kjellander,perkj,mflodman,henrika,asapersson,niklas.enbom

Review URL: https://webrtc-codereview.appspot.com/23129004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7726 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/test/testsupport/packet_reader_unittest.cc b/webrtc/test/testsupport/packet_reader_unittest.cc
index 83cde69..2679be4 100644
--- a/webrtc/test/testsupport/packet_reader_unittest.cc
+++ b/webrtc/test/testsupport/packet_reader_unittest.cc
@@ -26,11 +26,11 @@
   void TearDown() {
     delete reader_;
   }
-  void VerifyPacketData(int expected_length,
+  void VerifyPacketData(size_t expected_length,
                         int actual_length,
                         uint8_t* original_data_pointer,
                         uint8_t* new_data_pointer) {
-    EXPECT_EQ(expected_length, actual_length);
+    EXPECT_EQ(static_cast<int>(expected_length), actual_length);
     EXPECT_EQ(*original_data_pointer, *new_data_pointer);
     EXPECT_EQ(0, memcmp(original_data_pointer, new_data_pointer,
                         actual_length));
@@ -82,7 +82,7 @@
   // Reading another one shall result in 0 bytes:
   length_to_read = reader_->NextPacket(&data_pointer);
   EXPECT_EQ(0, length_to_read);
-  EXPECT_EQ(kPacketSizeInBytes, data_pointer - data);
+  EXPECT_EQ(kPacketSizeInBytes, static_cast<size_t>(data_pointer - data));
 }
 
 // Test with data length that will result in 3 packets
@@ -105,7 +105,8 @@
   // Reading another one shall result in 0 bytes:
   length_to_read = reader_->NextPacket(&packet_data_pointer_);
   EXPECT_EQ(0, length_to_read);
-  EXPECT_EQ(kPacketDataLength, packet_data_pointer_ - packet_data_);
+  EXPECT_EQ(kPacketDataLength,
+            static_cast<size_t>(packet_data_pointer_ - packet_data_));
 }
 
 // Test with empty data.