import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

parser/html/nsHtml5ByteReadable.h

@@ -0,0 +1,33 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsHtml5ByteReadable_h
+#define nsHtml5ByteReadable_h
+
+/**
+ * A weak reference wrapper around a byte array.
+ */
+class nsHtml5ByteReadable
+{
+  public:
+
+    nsHtml5ByteReadable(const uint8_t* aCurrent, const uint8_t* aEnd)
+     : current(aCurrent),
+       end(aEnd)
+    {
+    }
+
+    inline int32_t read() {
+      if (current < end) {
+        return *(current++);
+      } else {
+        return -1;
+      }
+    }
+
+  private:
+    const uint8_t* current;
+    const uint8_t* end;
+};
+#endif