work in progress: observable implementation using detailed change records

lib/src/info.dart

Index: lib/src/info.dart
diff --git a/lib/src/info.dart b/lib/src/info.dart
index e69f6973219b58219be824253628a66b8f3fdd7e..7d3d347c4b455303946682ff50f6b2e434f683ae 100644
--- a/lib/src/info.dart
+++ b/lib/src/info.dart
@@ -161,7 +161,7 @@ typedef String NameMangler(String name, String suffix, [bool forceSuffix]);
 abstract class LibraryInfo {
 
   /** Whether there is any code associated with the page/component. */
-  bool get codeAttached => inlinedCode != null || externalFile != null;
+  bool get codeAttached => userCode != null || externalFile != null;
 
   /**
    * The actual code, either inlined or from an external file, or `null` if none
@@ -169,15 +169,18 @@ abstract class LibraryInfo {
    */
   DartCodeInfo userCode;
 
-  /** The inlined code, if any. */
-  String inlinedCode;
-
   /** The name of the file sourced in a script tag, if any. */
   Path externalFile;
 
   /** Info asscociated with [externalFile], if any. */
   FileInfo externalCode;
 
+  /**
+   * The inverse of [externalCode]. If this .dart file was imported via a script
+   * tag, this refers to the HTML file that imported it.
+   */
+  FileInfo htmlFile;
+
   /** File where the top-level code was defined. */
   Path get inputPath;
 
@@ -187,6 +190,15 @@ abstract class LibraryInfo {
    */
   String _getOutputFilename(NameMangler mangle);
 
+  /** This is used in transforming Dart code to track modified files. */
+  bool modified = false;
+
+  /**
+   * This is used in transforming Dart code to compute files that reference
+   * [modified] files.
+   */
+  List<FileInfo> referencedBy = [];
+
   /**
    * Components used within this library unit. For [FileInfo] these are
    * components used directly in the page. For [ComponentInfo] these are
@@ -636,7 +648,7 @@ class DartCodeInfo {
   final List<DartDirectiveInfo> directives;
 
   /** The rest of the code. */
-  final String code;
+  String code;
 
   DartCodeInfo(this.libraryName, this.partOf, this.directives, this.code);
 }
@@ -658,6 +670,9 @@ class DartDirectiveInfo {
   /** Shown identifiers. */
   List<String> show;
 
+  /** True if this directive should refer to a generated file. */
+  bool generated = false;
+
   DartDirectiveInfo(this.label, this.uri, [this.prefix, this.hide, this.show]);
 }