Add printing.dll to the component build.

printing/printed_page.h

Index: printing/printed_page.h
===================================================================
--- printing/printed_page.h	(revision 99019)
+++ printing/printed_page.h	(working copy)
@@ -19,7 +19,8 @@
 // Note: May be accessed from many threads at the same time. This is an non
 // issue since this object is immutable. The reason is that a page may be
 // printed and be displayed at the same time.
-class PrintedPage : public base::RefCountedThreadSafe<PrintedPage> {
+class PRINTING_EXPORT PrintedPage
+    : public base::RefCountedThreadSafe<PrintedPage> {
  public:
   PrintedPage(int page_number,
               Metafile* metafile,