[PDF] Rewind the font stream if font subsetting fails.

R=edisonn@google.com

Review URL: https://codereview.chromium.org/23654012

git-svn-id: http://skia.googlecode.com/svn/trunk@11116 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pdf/SkPDFFont.cpp b/src/pdf/SkPDFFont.cpp
index 6f108a8..7d8c286 100644
--- a/src/pdf/SkPDFFont.cpp
+++ b/src/pdf/SkPDFFont.cpp
@@ -582,6 +582,7 @@
         *fontStream = subsetFontStream;
         return fontSize;
     }
+    fontData->rewind();
 #else
     sk_ignore_unused_variable(fontName);
     sk_ignore_unused_variable(subset);