Reuse PrintContext to excessively triggering matchMedia('print') listeners.

webkit/glue/webkit_glue.cc

Index: webkit/glue/webkit_glue.cc
diff --git a/webkit/glue/webkit_glue.cc b/webkit/glue/webkit_glue.cc
index cb8d05f947b9d81becfe087d950b4cc1e1a09137..ea8b08bb985bd4b1ea1a0917dd6275cf099fbee7 100644
--- a/webkit/glue/webkit_glue.cc
+++ b/webkit/glue/webkit_glue.cc
@@ -154,7 +154,8 @@ int NumberOfPages(WebFrame* web_frame,
                   float page_height_in_pixels) {
   WebSize size(static_cast<int>(page_width_in_pixels),
                static_cast<int>(page_height_in_pixels));
-  int number_of_pages = web_frame->printBegin(size);
+  web_frame->printBegin();
+  int number_of_pages = web_frame->setPageSizeResolution(size);
   web_frame->printEnd();
   return number_of_pages;
 }