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/talk/media/webrtc/webrtcvoiceengine.h b/talk/media/webrtc/webrtcvoiceengine.h
index 67fadc5..6dc1f25 100644
--- a/talk/media/webrtc/webrtcvoiceengine.h
+++ b/talk/media/webrtc/webrtcvoiceengine.h
@@ -69,7 +69,7 @@
   }
   void set_loop(bool loop) { loop_ = loop; }
 
-  virtual int Read(void* buf, int len) OVERRIDE;
+  virtual int Read(void* buf, size_t len) OVERRIDE;
   virtual int Rewind() OVERRIDE;
 
  private:
@@ -80,7 +80,7 @@
 // WebRtcMonitorStream is used to monitor a stream coming from WebRtc.
 // For now we just dump the data.
 class WebRtcMonitorStream : public webrtc::OutStream {
-  virtual bool Write(const void *buf, int len) OVERRIDE {
+  virtual bool Write(const void *buf, size_t len) OVERRIDE {
     return true;
   }
 };
@@ -315,17 +315,16 @@
 
  protected:
   // implements Transport interface
-  virtual int SendPacket(int channel, const void *data, int len) OVERRIDE {
+  virtual int SendPacket(int channel, const void *data, size_t len) OVERRIDE {
     rtc::Buffer packet(data, len, kMaxRtpPacketLen);
-    if (!T::SendPacket(&packet)) {
-      return -1;
-    }
-    return len;
+    return T::SendPacket(&packet) ? static_cast<int>(len) : -1;
   }
 
-  virtual int SendRTCPPacket(int channel, const void *data, int len) OVERRIDE {
+  virtual int SendRTCPPacket(int channel,
+                             const void* data,
+                             size_t len) OVERRIDE {
     rtc::Buffer packet(data, len, kMaxRtpPacketLen);
-    return T::SendRtcp(&packet) ? len : -1;
+    return T::SendRtcp(&packet) ? static_cast<int>(len) : -1;
   }
 
  private: