Add separate scanner only intended for preparsing.

src/scanner.cc

Index: src/scanner.cc
diff --git a/src/scanner.cc b/src/scanner.cc
index f7e7db38e332decc91d56b26cd25ad0e5876b3fd..803d9589dcbb89dd518242efe7eed04665e5eeb9 100755
--- a/src/scanner.cc
+++ b/src/scanner.cc
@@ -38,7 +38,7 @@ namespace internal {
 // ----------------------------------------------------------------------------
 // UTF8Buffer
 
-UTF8Buffer::UTF8Buffer() : buffer_(kInitialCapacity) { }
+UTF8Buffer::UTF8Buffer() : buffer_(kInitialCapacity), recording_(false) { }
 
 
 UTF8Buffer::~UTF8Buffer() {}
@@ -123,55 +123,6 @@ void CharacterStreamUTF16Buffer::SeekForward(int pos) {
 }
 
 
-// ExternalStringUTF16Buffer
-template <typename StringType, typename CharType>
-ExternalStringUTF16Buffer<StringType, CharType>::ExternalStringUTF16Buffer()
-    : raw_data_(NULL) { }
-
-
-template <typename StringType, typename CharType>
-void ExternalStringUTF16Buffer<StringType, CharType>::Initialize(
-     Handle<StringType> data,
-     int start_position,
-     int end_position) {
-  ASSERT(!data.is_null());
-  raw_data_ = data->resource()->data();
-
-  ASSERT(end_position <= data->length());
-  if (start_position > 0) {
-    SeekForward(start_position);
-  }
-  end_ =
-      end_position != Scanner::kNoEndPosition ? end_position : data->length();
-}
-
-
-template <typename StringType, typename CharType>
-uc32 ExternalStringUTF16Buffer<StringType, CharType>::Advance() {
-  if (pos_ < end_) {
-    return raw_data_[pos_++];
-  } else {
-    // note: currently the following increment is necessary to avoid a
-    // test-parser problem!
-    pos_++;
-    return static_cast<uc32>(-1);
-  }
-}
-
-
-template <typename StringType, typename CharType>
-void ExternalStringUTF16Buffer<StringType, CharType>::PushBack(uc32 ch) {
-  pos_--;
-  ASSERT(pos_ >= Scanner::kCharacterLookaheadBufferSize);
-  ASSERT(raw_data_[pos_ - Scanner::kCharacterLookaheadBufferSize] == ch);
-}
-
-
-template <typename StringType, typename CharType>
-void ExternalStringUTF16Buffer<StringType, CharType>::SeekForward(int pos) {
-  pos_ = pos;
-}
-
 // ----------------------------------------------------------------------------
 // Scanner::LiteralScope