Fixed more fuzzer issues

src/core/SkValidatingReadBuffer.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkErrorInternals.h"
 #include "SkValidatingReadBuffer.h"
@@ skipping 210 matching lines @@
     }
     bitmap->unflatten(*this);
     this->validate((bitmap->width() == width) && (bitmap->height() == height));
 }
 
 SkTypeface* SkValidatingReadBuffer::readTypeface() {
     // TODO: Implement this (securely) when needed
     return NULL;
 }
 
+bool SkValidatingReadBuffer::validateAvailable(size_t size) {
+    return this->validate((size <= SK_MaxU32) && fReader.isAvailable(static_cast<uint32_t>(size)));
+}
+
 SkFlattenable* SkValidatingReadBuffer::readFlattenable(SkFlattenable::Type type) {
     SkString name;
     this->readString(&name);
     if (fError) {
         return NULL;
     }
 
     // Is this the type we wanted ?
     const char* cname = name.c_str();
     SkFlattenable::Type baseType;
@@ skipping 21 matching lines @@
             delete obj;
             obj = NULL;
         }
     } else {
         // we must skip the remaining data
         this->skip(sizeRecorded);
         SkASSERT(false);
     }
     return obj;
 }