[webcodecs] Fix description for video encoder interface.

Bug: None
Change-Id: Id361efb087daf048b5a360e73b57a59a97c1691c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2525901Reviewed-by: Dan Sanders <sandersd@chromium.org>
Commit-Queue: Chunbo Hua <chunbo.hua@intel.com>
Cr-Commit-Position: refs/heads/master@{#825616}

third_party/blink/renderer/modules/webcodecs/video_encoder.idl

@@ -11,7 +11,7 @@
     [CallWith=ScriptState, RaisesException, MeasureAs=WebCodecsVideoEncoder]
     constructor(VideoEncoderInit init);
 
-    // The number of pending decode requests. This does not include requests that
+    // The number of pending encode requests. This does not include requests that
     // have been sent to the underlying codec.
     //
     // Applications can minimize underflow by enqueueing encode requests until
@@ -55,6 +55,6 @@
     [RaisesException]
     void close();
 
-    // Which state the decoder is in, indicating which methods can be called.
+    // Which state the encoder is in, indicating which methods can be called.
     readonly attribute CodecState state;
 };