fix(metadata_extractor): Do not try to guess the selector

The dynamic version of angular mandates that the selector is specified.
This commit makes the static vesion consistent with that behavior, the
selector must always be explicitely specified.

lib/tools/source_metadata_extractor.dart

@@ -4,9 +4,6 @@ import 'package:analyzer/src/generated/ast.dart';
 import 'package:angular/tools/source_crawler.dart';
 import 'package:angular/tools/common.dart';
 
-const String _COMPONENT = '-component';
-const String _DIRECTIVE = '-directive';
-String _ATTR_DIRECTIVE = '-attr' + _DIRECTIVE;
 RegExp _ATTR_SELECTOR_REGEXP = new RegExp(r'\[([^\]]+)\]');
 const List<String> _specs = const ['=>!', '=>', '<=>', '@', '&'];
 const Map<String, String> _attrAnnotationsToSpec = const {
@@ -70,27 +67,9 @@ class SourceMetadataExtractor {
 
       // No explicit selector specified on the directive, compute one.
       var className = meta.className;
+
       if (dirInfo.selector == null) {
-        if (meta.type == COMPONENT) {
-          if (className.endsWith(_COMPONENT)) {
-            dirInfo.selector = className.
-                substring(0, className.length - _COMPONENT.length);
-          } else {
-            throw "Directive name '$className' must end with $_DIRECTIVE, "
-            "$_ATTR_DIRECTIVE, $_COMPONENT or have a \$selector field.";
-          }
-        } else {
-          if (className.endsWith(_ATTR_DIRECTIVE)) {
-            var attrName = className.
-                substring(0, className.length - _ATTR_DIRECTIVE.length);
-            dirInfo.selector = '[$attrName]';
-          } else if (className.endsWith(_DIRECTIVE)) {
-            dirInfo.selector = className.
-                substring(0, className.length - _DIRECTIVE.length);
-          } else {
-            throw "Directive name '$className' must have a \$selector field.";
-          }
-        }
+        throw new ArgumentError('Missing selector annotation for $className');
       }
       var reprocessedAttrs = <String>[];
       dirInfo.expressionAttrs.forEach((String attr) {