Simply PDF text extraction

Removing some obsolete conditional code,
which was necessary for some obsolete version
of PDF.js.

Fortunately, by now, all supported versions
of PDF.js uses the same data format, so this
workaround can go.

h/static/scripts/annotator/plugin/pdf.coffee

@@ -152,12 +152,8 @@ class window.PDFTextMapper extends PageTextMapperCore
       # Wait for the data to be extracted
       page.getTextContent().then (data) =>
 
-        # There is some variation about what I might find here,
-        # depending on PDF.js version, so we need to do some guesswork.
-        textData = data.bidiTexts ? data.items ? data
-
         # First, join all the pieces from the bidiTexts
-        rawContent = (text.str for text in textData).join " "
+        rawContent = (text.str for text in data.items).join " "
 
         # Do some post-processing
         content = @_parseExtractedText rawContent