Revert "Switch FE to use the libraries.json format."

pkg/front_end/lib/src/base/processed_options.dart

Index: pkg/front_end/lib/src/base/processed_options.dart
diff --git a/pkg/front_end/lib/src/base/processed_options.dart b/pkg/front_end/lib/src/base/processed_options.dart
index 5ba11fafdd27691e5164e47c15ad44b4838a153a..ea1d6ac526b132e1c77ef3fecc461f75f8c43489 100644
--- a/pkg/front_end/lib/src/base/processed_options.dart
+++ b/pkg/front_end/lib/src/base/processed_options.dart
@@ -28,8 +28,6 @@ import 'package:source_span/source_span.dart' show SourceSpan, SourceLocation;
 import 'package:front_end/src/fasta/command_line_reporting.dart'
     as command_line_reporting;
 
-import 'libraries_specification.dart';
-
 /// All options needed for the front end implementation.
 ///
 /// This includes: all of [CompilerOptions] in a form useful to the
@@ -78,22 +76,10 @@ class ProcessedOptions {
   /// The location of the SDK, or `null` if the location hasn't been determined
   /// yet.
   Uri _sdkRoot;
-  Uri get sdkRoot {
-    _ensureSdkDefaults();
-    return _sdkRoot;
-  }
+  Uri get sdkRoot => _sdkRoot ??= _normalizeSdkRoot();
 
   Uri _sdkSummary;
-  Uri get sdkSummary {
-    _ensureSdkDefaults();
-    return _sdkSummary;
-  }
-
-  Uri _librariesSpecificationUri;
-  Uri get librariesSpecificationUri {
-    _ensureSdkDefaults();
-    return _librariesSpecificationUri;
-  }
+  Uri get sdkSummary => _sdkSummary ??= _computeSdkSummaryUri();
 
   Ticker ticker;
 
@@ -288,45 +274,20 @@ class ProcessedOptions {
   /// required to locate/read the packages file as well as SDK metadata.
   Future<UriTranslatorImpl> getUriTranslator() async {
     if (_uriTranslator == null) {
-      ticker.logMs("Started building UriTranslator");
-      var libraries = await _computeLibrarySpecification();
-      ticker.logMs("Read libraries file");
-      var packages = await _getPackages();
+      await _getPackages();
+      // TODO(scheglov) Load SDK libraries from whatever format we decide.
+      // TODO(scheglov) Remove the field "_raw.dartLibraries".
+      var libraries = _raw.dartLibraries ?? await _parseDartLibraries();
+      _uriTranslator = new UriTranslatorImpl(
+          libraries, const <String, List<Uri>>{}, _packages);
       ticker.logMs("Read packages file");
-      _uriTranslator = new UriTranslatorImpl(libraries, packages);
     }
     return _uriTranslator;
   }
 
-  Future<TargetLibrariesSpecification> _computeLibrarySpecification() async {
-    var name = target.name;
-    // TODO(sigmund): Eek! We should get to the point where there is no
-    // fasta-specific targets and the target names are meaningful.
-    if (name.endsWith('_fasta')) name = name.substring(0, name.length - 6);
-
-    if (librariesSpecificationUri == null ||
-        !await fileSystem.entityForUri(librariesSpecificationUri).exists()) {
-      if (compileSdk) {
-        reportWithoutLocation(
-            templateSdkSpecificationNotFound
-                .withArguments(librariesSpecificationUri),
-            Severity.error);
-      }
-      return new TargetLibrariesSpecification(name);
-    }
-
-    var json =
-        await fileSystem.entityForUri(librariesSpecificationUri).readAsString();
-    try {
-      var spec =
-          await LibrariesSpecification.parse(librariesSpecificationUri, json);
-      return spec.specificationFor(name);
-    } on LibrariesSpecificationException catch (e) {
-      reportWithoutLocation(
-          templateCannotReadSdkSpecification.withArguments('${e.error}'),
-          Severity.error);
-      return new TargetLibrariesSpecification(name);
-    }
+  Future<Map<String, Uri>> _parseDartLibraries() async {
+    Uri librariesJson = _raw.sdkRoot?.resolve("lib/libraries.json");
+    return await computeDartLibraries(fileSystem, librariesJson);
   }
 
   /// Get the package map which maps package names to URIs.
@@ -437,42 +398,32 @@ class ProcessedOptions {
     return Packages.noPackages;
   }
 
-  bool _computedSdkDefaults = false;
-
-  /// Ensure [_sdkRoot], [_sdkSummary] and [_librarySpecUri] are initialized.
-  ///
-  /// If they are not set explicitly, they are infered based on the default
-  /// behavior described in [CompilerOptions].
-  void _ensureSdkDefaults() {
-    if (_computedSdkDefaults) return;
-    _computedSdkDefaults = true;
-    var root = _raw.sdkRoot;
-    if (root != null) {
-      // Normalize to always end in '/'
-      if (!root.path.endsWith('/')) {
-        root = root.replace(path: root.path + '/');
-      }
-      _sdkRoot = root;
-    } else if (compileSdk) {
+  /// Get the location of the SDK.
+  Uri _normalizeSdkRoot() {
+    // If an SDK summary location was provided, the SDK itself should not be
+    // needed.
+    assert(_raw.sdkSummary == null);
+    if (_raw.sdkRoot == null) {
       // TODO(paulberry): implement the algorithm for finding the SDK
       // automagically.
-      unimplemented('infer the default sdk location', -1, null);
+      return unimplemented('infer the default sdk location', -1, null);
     }
-
-    if (_raw.sdkSummary != null) {
-      _sdkSummary = _raw.sdkSummary;
-    } else if (!compileSdk) {
-      // Infer based on the sdkRoot, but only when `compileSdk` is false,
-      // otherwise the default intent was to compile the sdk from sources and
-      // not to load an sdk summary file.
-      _sdkSummary = root?.resolve('outline.dill');
+    var root = _raw.sdkRoot;
+    if (!root.path.endsWith('/')) {
+      root = root.replace(path: root.path + '/');
     }
+    return root;
+  }
 
-    if (_raw.librariesSpecificationUri != null) {
-      _librariesSpecificationUri = _raw.librariesSpecificationUri;
-    } else if (compileSdk) {
-      _librariesSpecificationUri = sdkRoot.resolve('lib/libraries.json');
-    }
+  /// Get or infer the location of the SDK summary.
+  Uri _computeSdkSummaryUri() {
+    if (_raw.sdkSummary != null) return _raw.sdkSummary;
+
+    // Infer based on the sdkRoot, but only when `compileSdk` is false,
+    // otherwise the default intent was to compile the sdk from sources and not
+    // to load an sdk summary file.
+    if (_raw.compileSdk) return null;
+    return sdkRoot.resolve('outline.dill');
   }
 
   /// Create a [FileSystem] specific to the current options.
@@ -543,8 +494,6 @@ class ProcessedOptions {
 
     sb.writeln('Compile SDK: ${compileSdk}');
     sb.writeln('SDK root: ${_sdkRoot} (provided: ${_raw.sdkRoot})');
-    sb.writeln('SDK specification: ${_librariesSpecificationUri} '
-        '(provided: ${_raw.librariesSpecificationUri})');
     sb.writeln('SDK summary: ${_sdkSummary} (provided: ${_raw.sdkSummary})');
 
     sb.writeln('Strong: ${strongMode}');