clean up non-ASCII comments

Change-Id: I07ad00133f6a938de70a94024a0ebe36c6c542bb
Reviewed-on: https://skia-review.googlesource.com/6524
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Hal Canary <halcanary@google.com>
diff --git a/src/pdf/SkPDFMetadata.cpp b/src/pdf/SkPDFMetadata.cpp
index 4206884..ee5c19b 100644
--- a/src/pdf/SkPDFMetadata.cpp
+++ b/src/pdf/SkPDFMetadata.cpp
@@ -164,7 +164,7 @@
         stream->write(streamBegin, strlen(streamBegin));
         // Do not compress this.  The standard requires that a
         // program that does not understand PDF can grep for
-        // "<?xpacket" and extracť the entire XML.
+        // "<?xpacket" and extract the entire XML.
         stream->write(fXML.c_str(), fXML.size());
         static const char streamEnd[] = "\nendstream";
         stream->write(streamEnd, strlen(streamEnd));