use validating readbuffer

Bug:784869
Change-Id: Iaf43e14ec2ad72d061e7de25364fb481229d7651
Reviewed-on: https://skia-review.googlesource.com/71764
Commit-Queue: Mike Reed <reed@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
diff --git a/src/core/SkTextBlob.cpp b/src/core/SkTextBlob.cpp
index ebd73a9..c6325df 100644
--- a/src/core/SkTextBlob.cpp
+++ b/src/core/SkTextBlob.cpp
@@ -7,7 +7,7 @@
 
 #include "SkTextBlobRunIterator.h"
 
-#include "SkReadBuffer.h"
+#include "SkValidatingReadBuffer.h"
 #include "SkTypeface.h"
 #include "SkWriteBuffer.h"
 
@@ -840,11 +840,11 @@
     return data;
 }
 
-class SkTypefaceResolverReadBuffer : public SkReadBuffer {
+class SkTypefaceResolverReadBuffer : public SkValidatingReadBuffer {
 public:
     SkTypefaceResolverReadBuffer(const void* data, size_t size, SkTypefaceResolverProc proc,
                                  void* ctx)
-        : SkReadBuffer(data, size)
+        : SkValidatingReadBuffer(data, size)
         , fResolverProc(proc)
         , fResolverCtx(ctx)
     {}