Enhanced documentation. Replaced DCHECK with CHECK.

R=kwiberg@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/34309004

Cr-Commit-Position: refs/heads/master@{#8461}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8461 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
index 27c3e6a..2b5b690 100644
--- a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
+++ b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
@@ -78,7 +78,7 @@
   }
   CHECK_EQ(speech_buffer_.size(), static_cast<size_t>(full_frame_samples_));
   int16_t ret = EncodeCall(&speech_buffer_[0], full_frame_samples_, encoded);
-  DCHECK_GE(ret, 0);
+  CHECK_GE(ret, 0);
   speech_buffer_.clear();
   info->encoded_timestamp = first_timestamp_in_buffer_;
   info->payload_type = payload_type_;
diff --git a/webrtc/modules/audio_coding/codecs/g711/include/g711_interface.h b/webrtc/modules/audio_coding/codecs/g711/include/g711_interface.h
index aa3894d..0b798a6 100644
--- a/webrtc/modules/audio_coding/codecs/g711/include/g711_interface.h
+++ b/webrtc/modules/audio_coding/codecs/g711/include/g711_interface.h
@@ -34,8 +34,8 @@
  * Output:
  *      - encoded            : The encoded data vector
  *
- * Return value              : >0 - Length (in bytes) of coded data
- *                             -1 - Error
+ * Return value              : Length (in bytes) of coded data.
+ *                             Always equal to len input parameter.
  */
 
 int16_t WebRtcG711_EncodeA(const int16_t* speechIn,
@@ -55,8 +55,8 @@
  * Output:
  *      - encoded            : The encoded data vector
  *
- * Return value              : >0 - Length (in bytes) of coded data
- *                             -1 - Error
+ * Return value              : Length (in bytes) of coded data.
+ *                             Always equal to len input parameter.
  */
 
 int16_t WebRtcG711_EncodeU(const int16_t* speechIn,
diff --git a/webrtc/modules/audio_coding/codecs/pcm16b/include/pcm16b.h b/webrtc/modules/audio_coding/codecs/pcm16b/include/pcm16b.h
index 49b4614..1cdf92d 100644
--- a/webrtc/modules/audio_coding/codecs/pcm16b/include/pcm16b.h
+++ b/webrtc/modules/audio_coding/codecs/pcm16b/include/pcm16b.h
@@ -32,7 +32,8 @@
  * Output:
  *              - encoded       : Encoded data vector (big endian 16 bit)
  *
- * Returned value               : Size in bytes of encoded
+ * Returned value               : Length (in bytes) of coded data.
+ *                                Always equal to twice the len input parameter.
  */
 
 int16_t WebRtcPcm16b_Encode(const int16_t* speech,