Fix comments in common_types.h

Two of the metrics in NetworkStatistics were desribed as being in
percent, while they are in fact fractions between 0 and 1, scaled
to Q14 domain.

R=tina.legrand@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/30689004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7411 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/common_types.h b/webrtc/common_types.h
index 05e1faf..e607ddc 100644
--- a/webrtc/common_types.h
+++ b/webrtc/common_types.h
@@ -337,9 +337,9 @@
     uint16_t preferredBufferSize;
     // adding extra delay due to "peaky jitter"
     bool jitterPeaksFound;
-    // loss rate (network + late) in percent (in Q14)
+    // Loss rate (network + late); fraction between 0 and 1, scaled to Q14.
     uint16_t currentPacketLossRate;
-    // late loss rate in percent (in Q14)
+    // Late loss rate; fraction between 0 and 1, scaled to Q14.
     uint16_t currentDiscardRate;
     // fraction (of original stream) of synthesized speech inserted through
     // expansion (in Q14)