Inline the setup method in the parse method in `src/core/document…

….js`

Now that the `parse` method is simplified we can inline the `setup`
method in the `parse` method since it's only two lines of code. This
avoids some indirection.

src/core/document.js

@@ -573,7 +573,8 @@ class PDFDocument {
   }
 
   parse(recoveryMode) {
-    this.setup(recoveryMode);
+    this.xref.parse(recoveryMode);
+    this.catalog = new Catalog(this.pdfManager, this.xref);
 
     // The `checkHeader` method is called before this method and parses the
     // version from the header. The specification states in section 7.5.2
@@ -676,11 +677,6 @@ class PDFDocument {
     this.xref.setStartXRef(this.startXRef);
   }
 
-  setup(recoveryMode) {
-    this.xref.parse(recoveryMode);
-    this.catalog = new Catalog(this.pdfManager, this.xref);
-  }
-
   get numPages() {
     const linearization = this.linearization;
     const num = linearization ? linearization.numPages : this.catalog.numPages;