Implement DPI for perspective bitmaps in PDF - we save the bitmap at the resolution requested.

include/pdf/SkPDFDevice.h

Index: include/pdf/SkPDFDevice.h
diff --git a/include/pdf/SkPDFDevice.h b/include/pdf/SkPDFDevice.h
index d8e1aa283f80ca84b18a75921cace94b372c351b..2243dde22b6c65041ef5ebbbd6e282544b11e8dc 100644
--- a/include/pdf/SkPDFDevice.h
+++ b/include/pdf/SkPDFDevice.h
@@ -191,11 +191,6 @@ public:
         return *(fFontGlyphUsage.get());
     }
 
-protected:
-    virtual bool onReadPixels(const SkBitmap& bitmap, int x, int y,
-                              SkCanvas::Config8888) SK_OVERRIDE;
-
-    virtual bool allowImageFilter(SkImageFilter*) SK_OVERRIDE;
 
     /**
      *  rasterDpi - the DPI at which features without native PDF support
@@ -211,6 +206,12 @@ protected:
         fRasterDpi = rasterDpi;
     }
 
+protected:
+    virtual bool onReadPixels(const SkBitmap& bitmap, int x, int y,
+                              SkCanvas::Config8888) SK_OVERRIDE;
+
+    virtual bool allowImageFilter(SkImageFilter*) SK_OVERRIDE;
+
 private:
     // TODO(vandebo): push most of SkPDFDevice's state into a core object in
     // order to get the right access levels without using friend.