Refactor some source position info

src/messages.js

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 163 matching lines @@
 // Helper functions; called from the runtime system.
 function FormatMessage(message) {
   var format = kMessages[message.type];
   if (!format) return "<unknown message " + message.type + ">";
   return FormatString(format, message.args);
 }
 
 
 function GetLineNumber(message) {
   if (message.startPos == -1) return -1;
-  var location = message.script.locationFromPosition(message.startPos);
+  var location = message.script.locationFromPosition(message.startPos, true);
   if (location == null) return -1;
   return location.line + 1;
 }
 
 
 // Returns the source code line containing the given source
 // position, or the empty string if the position is invalid.
 function GetSourceLine(message) {
-  var location = message.script.locationFromPosition(message.startPos);
+  var location = message.script.locationFromPosition(message.startPos, true);
   if (location == null) return "";
   location.restrict();
   return location.sourceText();
 }
 
 
 function MakeTypeError(type, args) {
   return MakeGenericError($TypeError, type, args);
 }
 
@@ skipping 19 matching lines @@
 
 
 function MakeError(type, args) {
   return MakeGenericError($Error, type, args);
 }
 
 
 /**
  * Get information on a specific source position.
  * @param {number} position The source position
+ * @param {boolean} include_resource_offset Set to true to have the resource
+ *     offset added to the location
  * @return {SourceLocation}
  *     If line is negative or not in the source null is returned.
  */
-Script.prototype.locationFromPosition = function (position) {
+Script.prototype.locationFromPosition = function (position,
+                                                  include_resource_offset) {
   var lineCount = this.lineCount();
   var line = -1;
   if (position <= this.line_ends[0]) {
     line = 0;
   } else {
     for (var i = 1; i < lineCount; i++) {
       if (this.line_ends[i - 1] < position && position <= this.line_ends[i]) {
         line = i;
         break;
       }
     }
   }
 
   if (line == -1) return null;
 
   // Determine start, end and column.
   var start = line == 0 ? 0 : this.line_ends[line - 1] + 1;
   var end = this.line_ends[line];
   if (end > 0 && this.source.charAt(end - 1) == '\r') end--;
   var column = position - start;
 
   // Adjust according to the offset within the resource.
-  line += this.line_offset;
-  if (line == this.line_offset) {
-    column += this.column_offset;
+  if (include_resource_offset) {
+    line += this.line_offset;
+    if (line == this.line_offset) {
+      column += this.column_offset;
+    }
   }
 
   return new SourceLocation(this, position, line, column, start, end);
 };
 
 
 /**
  * Get information on a specific source line and column possibly offset by a
  * fixed source position. This function is used to find a source position from
  * a line and column position. The fixed source position offset is typically
@@ skipping 294 matching lines @@
       result += ToDetailString(recv) + ".";
     result += GetFunctionName(fun, recv);
   }
   if (pos != -1) {
     var script = %FunctionGetScript(fun);
     var file;
     if (script) {
       file = %FunctionGetScript(fun).data;
     }
     if (file) {
-      var location = %FunctionGetScript(fun).locationFromPosition(pos);
+      var location = %FunctionGetScript(fun).locationFromPosition(pos, true);
       if (!isTopLevel) result += "(";
       result += file;
       if (location != null) {
         result += ":" + (location.line + 1) + ":" + (location.column + 1);
       }
       if (!isTopLevel) result += ")";
     }
   }
   return (result) ? "    at " + result : result;
 }
@@ skipping 75 matching lines @@
     return this.name + ": " + FormatMessage({ type: type, args: this.arguments });
   }
   var message = this.message;
   return this.name + (message ? (": " + message) : "");
 }, DONT_ENUM);
 
 
 // Boilerplate for exceptions for stack overflows. Used from
 // Top::StackOverflow().
 const kStackOverflowBoilerplate = MakeRangeError('stack_overflow', []);