Remove VideoFrameType aliases for FrameType.

No longer used in Chromium, so these can now be removed.

BUG=webrtc:5042
R=mflodman@webrtc.org
TBR=magjed@webrtc.org

Review URL: https://codereview.webrtc.org/1415693002 .

Cr-Commit-Position: refs/heads/master@{#10390}

talk/app/webrtc/java/jni/androidmediadecoder_jni.cc

@@ -474,7 +474,7 @@ int32_t MediaCodecVideoDecoder::Decode(
 
   // Always start with a complete key frame.
   if (key_frame_required_) {
-    if (inputImage._frameType != webrtc::kKeyFrame) {
+    if (inputImage._frameType != webrtc::kVideoFrameKey) {
       ALOGE << "Decode() - key frame is required";
       return WEBRTC_VIDEO_CODEC_ERROR;
     }