[parser] implement error reporting for Scanner errors

src/parsing/scanner.h

Index: src/parsing/scanner.h
diff --git a/src/parsing/scanner.h b/src/parsing/scanner.h
index 53742c0b4bdb06363814c3248b18a7865b46c6be..5b943e2974bae1f57d5cf4255eeaead16dfb689c 100644
--- a/src/parsing/scanner.h
+++ b/src/parsing/scanner.h
@@ -14,6 +14,7 @@
 #include "src/globals.h"
 #include "src/hashmap.h"
 #include "src/list.h"
+#include "src/messages.h"
 #include "src/parsing/token.h"
 #include "src/unicode.h"
 #include "src/unicode-decoder.h"
@@ -354,6 +355,10 @@ class Scanner {
   // (the token last returned by Next()).
   Location location() const { return current_.location; }
 
+  bool has_error() const { return scanner_error_ != MessageTemplate::kNone; }
+  MessageTemplate::Template error() const { return scanner_error_; }
+  Location error_location() const { return scanner_error_location_; }
+
   // Similar functions for the upcoming token.
 
   // One token look-ahead (past the token returned by Next()).
@@ -482,6 +487,7 @@ class Scanner {
     current_.raw_literal_chars = NULL;
     next_next_.token = Token::UNINITIALIZED;
     found_html_comment_ = false;
+    scanner_error_ = MessageTemplate::kNone;
   }
 
   // Support BookmarkScope functionality.
@@ -492,6 +498,19 @@ class Scanner {
   void DropBookmark();
   static void CopyTokenDesc(TokenDesc* to, TokenDesc* from);
 
+  void ReportScannerError(const Location& location,
+                          MessageTemplate::Template error) {
+    if (has_error()) return;
+    scanner_error_ = error;
+    scanner_error_location_ = location;
+  }
+
+  void ReportScannerError(int pos, MessageTemplate::Template error) {
+    if (has_error()) return;
+    scanner_error_ = error;
+    scanner_error_location_ = Location(pos, pos + 1);
+  }
+
   // Literal buffer support
   inline void StartLiteral() {
     LiteralBuffer* free_buffer =
@@ -637,7 +656,7 @@ class Scanner {
     return current_.raw_literal_chars->is_one_byte();
   }
 
-  template <bool capture_raw>
+  template <bool capture_raw, bool unicode = false>
   uc32 ScanHexNumber(int expected_length);
   // Scan a number of any length but not bigger than max_value. For example, the
   // number can be 000000001, so it's very long in characters but its value is
@@ -769,6 +788,9 @@ class Scanner {
   bool found_html_comment_;
 
   bool allow_harmony_exponentiation_operator_;
+
+  MessageTemplate::Template scanner_error_;
+  Location scanner_error_location_;
 };
 
 }  // namespace internal