Change scanner buffers to not use utf-8.

src/utils.h

Index: src/utils.h
diff --git a/src/utils.h b/src/utils.h
index 62b8726b802ae30f8d0c64f9343d7849d3f98e9e..21e70d758e9df8e980fc439dbcafc3910e984f82 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -530,6 +530,24 @@ class Collector {
   }
 
 
+  // Add a contiguous block of elements and return a vector backed
+  // by the added block.
+  // A basic Collector will keep this vector valid as long as the Collector
+  // is alive.
+  inline Vector<T> AddBlock(Vector<const T> source) {
+    if (source.length() > current_chunk_.length() - index_) {
+      Grow(source.length());
+    }
+    T* position = current_chunk_.start() + index_;
+    index_ += source.length();
+    size_ += source.length();
+    for (int i = 0; i < source.length(); i++) {
+      position[i] = source[i];
+    }
+    return Vector<T>(position, source.length());
+  }
+
+
   // Write the contents of the collector into the provided vector.
   void WriteTo(Vector<T> destination) {
     ASSERT(size_ <= destination.length());