replace detach/getStream apis on dynamicwstream with SkData

http://codereview.appspot.com/4657046/



git-svn-id: http://skia.googlecode.com/svn/trunk@1714 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/pipe/SkGPipeWrite.cpp b/src/pipe/SkGPipeWrite.cpp
index 18c3e60..1ff7d45 100644
--- a/src/pipe/SkGPipeWrite.cpp
+++ b/src/pipe/SkGPipeWrite.cpp
@@ -16,6 +16,7 @@
 
 
 #include "SkCanvas.h"
+#include "SkData.h"
 #include "SkDevice.h"
 #include "SkPaint.h"
 #include "SkGPipe.h"
@@ -68,7 +69,8 @@
     size_t size = stream.getOffset();
     if (writer) {
         writer->write32(size);
-        writer->write(stream.getStream(), size);
+        SkAutoDataUnref data(stream.copyToData());
+        writer->write(data.data(), size);
     }
     return 4 + size;
 }