doc: Complete documentation for VideoStreams

Also quick clean up of the matching C++ files.

modules/theora/doc_classes/VideoStreamTheora.xml

@@ -1,8 +1,10 @@
 <?xml version="1.0" encoding="UTF-8" ?>
 <class name="VideoStreamTheora" inherits="VideoStream" category="Core" version="3.2">
 	<brief_description>
+		[VideoStream] resource for Ogg Theora videos.
 	</brief_description>
 	<description>
+		[VideoStream] resource handling the [url=https://www.theora.org/]Ogg Theora[/url] video format with [code].ogv[/code] extension.
 	</description>
 	<tutorials>
 	</tutorials>
@@ -11,6 +13,7 @@
 			<return type="String">
 			</return>
 			<description>
+				Returns the Ogg Theora video file handled by this [VideoStreamTheora].
 			</description>
 		</method>
 		<method name="set_file">
@@ -19,6 +22,7 @@
 			<argument index="0" name="file" type="String">
 			</argument>
 			<description>
+				Sets the Ogg Theora video file that this [VideoStreamTheora] resource handles. The [code]file[/code] name should have the [code].o[/code] extension.
 			</description>
 		</method>
 	</methods>

modules/theora/video_stream_theora.cpp

@@ -147,7 +147,6 @@ void VideoStreamPlaybackTheora::clear() {
 	thread = NULL;
 	ring_buffer.clear();
 #endif
-	//file_name = "";
 
 	theora_p = 0;
 	vorbis_p = 0;