pdfviewer: add --pages arg: render a certain page (all, all in desceding order, firsl, last and by page number)

Review URL: https://codereview.chromium.org/18584010

git-svn-id: http://skia.googlecode.com/svn/trunk@9999 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/experimental/PdfViewer/SkPdfRenderer.cpp b/experimental/PdfViewer/SkPdfRenderer.cpp
index 37867b4..f52d9a0 100644
--- a/experimental/PdfViewer/SkPdfRenderer.cpp
+++ b/experimental/PdfViewer/SkPdfRenderer.cpp
@@ -2013,7 +2013,7 @@
     return fPdfDoc->MediaBox(page);
 }
 
-size_t SkPdfRenderer::bytesUsed() {
+size_t SkPdfRenderer::bytesUsed() const {
     return fPdfDoc ? fPdfDoc->bytesUsed() : 0;
 }