Fixed some missing links in the documentation.

(cherry picked from commit da6e819b6f)

collects/htdp/error-reporting.scrbl

@@ -1,6 +1,8 @@
 #lang scribble/doc
 
-@(require scribble/manual)
+@(require scribble/manual
+          (for-label htdp/error)
+          )
 
 @title[#:tag "error-reporting"]{Error Reporting Functions} 
 

collects/htdp/error.rkt

@@ -114,7 +114,7 @@
 ;; check-arg : sym bool str (or/c str non-negative-integer) TST -> void
 (define (check-arg pname condition expected arg-posn given)
   (unless condition
-    (tp-error pname "expects a ~a as ~a argument, given: ~e"
+    (tp-error pname "expects a ~a as ~a argument, given ~e"
               expected 
               (spell-out arg-posn)
               given)))

collects/htdp/htdp-lib.scrbl

@@ -1,6 +1,7 @@
 #lang scribble/doc
 
-@(require scribble/manual scribble/eval)
+@(require scribble/manual scribble/eval
+          (for-label lang/prim lang/imageeq lang/posn racket/gui/base))
 @(define (htdp-ref s) @secref[#:doc '(lib "scribblings/htdp-langs/htdp-langs.scrbl") s])
 
 @title{HtDP Languages as Libraries}
@@ -72,7 +73,7 @@ libraries in legacy form. It provides the bindings of
 @defmodule[lang/plt-pretty-big]
 
 The @racketmodname[lang/plt-pretty-big] module extends
-@racket[lang/plt-pretty-big-text] with @racketmodname[scheme/gui/base]
+@racket[lang/plt-pretty-big-text] with @racketmodname[racket/gui/base]
 and @racketmodname[lang/imageeq].  This language corresponds to the
 @onscreen{Pretty Big} legacy language in DrRacket.
 

collects/htdp/testing.rkt

@@ -1,8 +1,8 @@
 #lang scheme/base
 
-(require test-engine/scheme-tests)
+(require test-engine/racket-tests)
 
 (define (generate-report) (test)#;(void))
 
-(provide (all-from-out test-engine/scheme-tests)
+(provide (all-from-out test-engine/racket-tests)
          generate-report)

collects/htdp/testing.scrbl

@@ -1,25 +1,26 @@
 #lang scribble/doc
 
-@(require scribble/manual)
+@(require scribble/manual
+          (for-label test-engine/racket-tests))
 
 @title{Testing} 
 
 @; -----------------------------------------------------------------------------
-@defmodule[htdp/testing #:use-sources (test-engine/scheme-tests)]
+@defmodule[htdp/testing #:use-sources (test-engine/racket-tests)]
 
-The library re-exports the following identifiers from test-engine/scheme-tests:
+The library re-exports the following identifiers from test-engine/racket-tests:
 
- @racket[build-test-engine]
- @racket[builder]
- @racket[display-results]
- @racket[error-handler]
- @racket[exn:fail:wish]
- @racket[generate-report]
- @racket[get-test-engine]
- @racket[reset-tests]
- @racket[run-tests]
- @racket[scheme-test-data]
- @racket[signature-test-info%]
+@defproc[(build-test-engine) void?]
+@defproc[(builder) void?]
+@defproc[(display-results) void?]
+@defproc[(error-handler) void?]
+@defproc[(exn:fail:wish) void?]
+@defproc[(generate-report) void?]
+@defproc[(get-test-engine) void?]
+@defproc[(reset-tests) void?]
+@defproc[(run-tests) void?]
+@defproc[(scheme-test-data) void?]
+@defproc[(signature-test-info%) void?]
 
 
 @(require scribble/eval