Move margin processing code to the browser process.

printing/page_setup.h

Index: printing/page_setup.h
diff --git a/printing/page_setup.h b/printing/page_setup.h
index 7f338931a62f95f007bfb0b992e9318bd01306f6..ef1552d0e73e1f2188a84f3b3721e4173d6a8d21 100644
--- a/printing/page_setup.h
+++ b/printing/page_setup.h
@@ -46,8 +46,12 @@ class PRINTING_EXPORT PageSetup {
   void Init(const gfx::Size& physical_size, const gfx::Rect& printable_area,
             int text_height);
 
+  // Use |requested_margins| as long as they fall inside the printable area.
   void SetRequestedMargins(const PageMargins& requested_margins);
 
+  // Ignore the printable area, and set the margins to |requested_margins|.
+  void ForceRequestedMargins(const PageMargins& requested_margins);
+
   // Flips the orientation of the page and recalculates all page areas.
   void FlipOrientation();
 
@@ -60,6 +64,10 @@ class PRINTING_EXPORT PageSetup {
   }
 
  private:
+  // Calculate overlay_area_, effective_margins_, and content_area_, based on
+  // a constraint of |bounds|.
+  void CalculateSizesWithinRect(const gfx::Rect& bounds);
+
   // Physical size of the page, including non-printable margins.
   gfx::Size physical_size_;