Enable VP8 encode for screenrecord

BZ: 161797

changing the mime name from "video/x-webm" to "video/x-vnd.on2.vp8" to
enable access VP8 HW encode via MediaCodec::CreateByType method.

Change-Id: I5fb77be40a651b47cc60e8a5f57019d46a6113ff
Signed-off-by: Liu Bolun <bolun.liu@intel.com>
diff --git a/videoencoder/VideoEncoderHost.cpp b/videoencoder/VideoEncoderHost.cpp
index 00a8e40..39b0e5d 100644
--- a/videoencoder/VideoEncoderHost.cpp
+++ b/videoencoder/VideoEncoderHost.cpp
@@ -53,7 +53,7 @@
         PVSoftMPEG4Encoder *p = new PVSoftMPEG4Encoder("OMX.google.mpeg4.encoder");
 #endif
         return (IVideoEncoder *)p;
-    } else if (strcasecmp(mimeType, "video/x-webm") == 0) {
+    } else if (strcasecmp(mimeType, "video/x-vnd.on2.vp8") == 0) {
         VideoEncoderVP8 *p = new VideoEncoderVP8();
         return (IVideoEncoder *)p;
     } else {