refactor(dart/transform): Avoid using package:code_transformers

Replace uses of `package:code_transformers`, which is only used to
convert from uri to `AssetId`, with calls to the utility methods in
`src/transform/common/url_resolver.dart`.

Closes #5931

modules/angular2/pubspec.yaml

@@ -11,7 +11,6 @@ environment:
 dependencies:
   analyzer: '>=0.24.4 <0.27.0'
   barback: '^0.15.2+2'
-  code_transformers: '0.2.9+4'
   dart_style: '>=0.1.8 <0.3.0'
   glob: '^1.0.0'
   html: '^0.12.0'
@@ -23,6 +22,7 @@ dependencies:
   source_span: '^1.0.0'
   stack_trace: '^1.1.1'
 dev_dependencies:
+  code_transformers: '0.2.9+4'
   guinness: '^0.1.18'
 transformers:
 - angular2

modules_dart/transform/lib/src/transform/common/class_matcher_base.dart

@@ -2,9 +2,10 @@ library angular2.transform.common.class_matcher_base;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:barback/barback.dart' show AssetId;
-import 'package:code_transformers/assets.dart';
 import 'package:path/path.dart' as path;
+
 import 'logging.dart' show log;
+import 'url_resolver.dart';
 
 /// Checks if a given [Identifier] matches any of the given [ClassDescriptor]s.
 abstract class ClassMatcherBase {
@@ -74,6 +75,7 @@ ImportDirective _getMatchingImport(
     name = className.name;
   }
   if (name != descriptor.name) return null;
+  final assetUri = toAssetUri(assetId);
   return (className.root as CompilationUnit)
       .directives
       .where((d) => d is ImportDirective)
@@ -82,12 +84,13 @@ ImportDirective _getMatchingImport(
     var uriString = i.uri.stringValue;
     if (uriString == descriptor.import) {
       importMatch = true;
-    } else if (uriString.startsWith('package:') ||
-        uriString.startsWith('dart:')) {
+    } else if (uriString.startsWith('package:') || isDartCoreUri(uriString)) {
       return false;
     } else {
-      importMatch =
-          descriptor.assetId == uriToAssetId(assetId, uriString, log, null);
+      final candidateAssetId =
+          fromUri(const TransformerUrlResolver().resolve(assetUri, uriString));
+
+      importMatch = descriptor.assetId == candidateAssetId;
     }
 
     if (!importMatch) return false;

modules_dart/transform/lib/src/transform/directive_processor/inliner.dart

@@ -4,14 +4,15 @@ import 'dart:async';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/src/generated/ast.dart';
-import 'package:angular2/src/transform/common/async_string_writer.dart';
-import 'package:angular2/src/transform/common/logging.dart';
-import 'package:code_transformers/assets.dart';
-import 'package:angular2/src/transform/common/asset_reader.dart';
 import 'package:barback/barback.dart' show AssetId;
 import 'package:source_span/source_span.dart';
 import 'package:path/path.dart' as path;
 
+import 'package:angular2/src/transform/common/asset_reader.dart';
+import 'package:angular2/src/transform/common/async_string_writer.dart';
+import 'package:angular2/src/transform/common/logging.dart';
+import 'package:angular2/src/transform/common/url_resolver.dart';
+
 /// Reads the code at `assetId`, inlining any `part` directives in that code.
 ///
 /// Returns `null` if the code represented by `assetId` is a `part`.
@@ -50,12 +51,13 @@ Future<String> _getAllDeclarations(AssetReader reader, AssetId assetId,
 
   var partsStart = visitor.parts.first.offset,
       partsEnd = visitor.parts.last.end;
+  final assetUri = toAssetUri(assetId);
 
   var asyncWriter = new AsyncStringWriter(code.substring(0, partsStart));
   visitor.parts.forEach((partDirective) {
     var uri = stringLiteralToString(partDirective.uri);
-    var partAssetId = uriToAssetId(assetId, uri, log, null /* span */,
-        errorOnAbsolute: false);
+    var partAssetId =
+        fromUri(const TransformerUrlResolver().resolve(assetUri, uri));
     asyncWriter.asyncPrint(reader.readAsString(partAssetId).then((partCode) {
       if (partCode == null || partCode.isEmpty) {
         log.warning('Empty part at "${partDirective.uri}. Ignoring.',