Random improvements in error reporting.

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

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
 
 import 'package:front_end/compilation_message.dart';
 import 'package:front_end/compiler_options.dart';
 import 'package:front_end/file_system.dart';
 import 'package:front_end/src/base/performace_logger.dart';
@@ skipping 155 matching lines @@
     for (var source in inputs) {
       // Note: we don't translate Uris at this point because some of the
       // validation further below must be done before we even construct an
       // UriTranslator
       // TODO(sigmund): consider validating dart/packages uri right after we
       // build the uri translator.
       if (source.scheme != 'dart' &&
           source.scheme != 'packages' &&
           !await fileSystem.entityForUri(source).exists()) {
         reportWithoutLocation(
-            templateInputFileNotFound.withArguments('$source'), Severity.error);
+            templateInputFileNotFound.withArguments(source), Severity.error);
         return false;
       }
     }
 
     if (_raw.sdkRoot != null &&
         !await fileSystem.entityForUri(sdkRoot).exists()) {
       reportWithoutLocation(
-          templateSdkRootNotFound.withArguments('$sdkRoot'), Severity.error);
+          templateSdkRootNotFound.withArguments(sdkRoot), Severity.error);
       return false;
     }
 
     var summary = sdkSummary;
     if (summary != null && !await fileSystem.entityForUri(summary).exists()) {
       reportWithoutLocation(
-          templateSdkSummaryNotFound.withArguments('$summary'), Severity.error);
+          templateSdkSummaryNotFound.withArguments(summary), Severity.error);
       return false;
     }
 
     if (compileSdk && summary != null) {
       reportWithoutLocation(
-          templateInternalProblemUnsupported.withArguments(
-              "The compileSdk and sdkSummary options are mutually exclusive"),
+          messageInternalProblemProvidedBothCompileSdkAndSdkSummary,
           Severity.internalProblem);
       return false;
     }
     return true;
   }
 
   /// Determine whether to generate code for the SDK when compiling a
   /// whole-program.
   bool get compileSdk => _raw.compileSdk;
 
@@ skipping 191 matching lines @@
   }
 
   /// 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.
-      return unimplemented('infer the default sdk location');
+      return unimplemented('infer the default sdk location', -1, null);
     }
     var root = _raw.sdkRoot;
     if (!root.path.endsWith('/')) {
       root = root.replace(path: root.path + '/');
     }
     return root;
   }
 
   /// Get or infer the location of the SDK summary.
   Uri _computeSdkSummaryUri() {
@@ skipping 131 matching lines @@
   String get dart2jsCode => _original.code.dart2jsCode;
 
   SourceSpan get span =>
       new SourceLocation(_original.charOffset, sourceUrl: _original.uri)
           .pointSpan();
 
   _CompilationMessage(this._original, this.severity);
 
   String toString() => message;
 }