adding set/get DPI calls for the pdf surface

gfx/thebes/public/gfxPDFSurface.h

@@ -40,8 +40,6 @@
 
 #include "gfxASurface.h"
 
-#include <cairo-pdf.h>
-
 class NS_EXPORT gfxPDFSurface : public gfxASurface {
     THEBES_DECL_ISUPPORTS_INHERITED
 
@@ -51,8 +49,12 @@ public:
                   double height_in_points);
     virtual ~gfxPDFSurface();
 
+    void SetDPI(double x, double y);
+    void GetDPI(double *xDPI, double *yDPI);
 
 private:
+    double mXDPI;
+    double mYDPI;
 };
 
 #endif /* GFX_WINDOWSSURFACE_H */

gfx/thebes/src/gfxPDFSurface.cpp

@@ -37,9 +37,12 @@
 
 #include "gfxPDFSurface.h"
 
+#include <cairo-pdf.h>
+
 THEBES_IMPL_REFCOUNTING(gfxPDFSurface)
 
 gfxPDFSurface::gfxPDFSurface(const char *filename, double width, double height)
+    : mXDPI(-1), mYDPI(-1)
 {
     Init(cairo_pdf_surface_create(filename, width, height));
 }
@@ -48,3 +51,18 @@ gfxPDFSurface::~gfxPDFSurface()
 {
     Destroy();
 }
+
+void
+gfxPDFSurface::SetDPI(double xDPI, double yDPI)
+{
+    mXDPI = xDPI;
+    mYDPI = yDPI;
+    cairo_pdf_surface_set_dpi(CairoSurface(), xDPI, yDPI);
+}
+
+void
+gfxPDFSurface::GetDPI(double *xDPI, double *yDPI)
+{
+    *xDPI = mXDPI;
+    *yDPI = mYDPI;
+}