Re-enable and add new HTML support

pkg/analyzer/lib/src/generated/error.dart

Index: pkg/analyzer/lib/src/generated/error.dart
diff --git a/pkg/analyzer/lib/src/generated/error.dart b/pkg/analyzer/lib/src/generated/error.dart
index 0881a7c63091762e62706e466edf27c076c4655e..c667af7933dd43a1a5071670d9add0456b5e99ee 100644
--- a/pkg/analyzer/lib/src/generated/error.dart
+++ b/pkg/analyzer/lib/src/generated/error.dart
@@ -3111,6 +3111,38 @@ class HintCode extends ErrorCode {
 }
 
 /**
+ * The error codes used for errors in HTML files. The convention for this
+ * class is for the name of the error code to indicate the problem that caused
+ * the error to be generated and for the error message to explain what is wrong
+ * and, when appropriate, how the problem can be corrected.
+ */
+class HtmlErrorCode extends ErrorCode {
+  /**
+   * An error code indicating that there is a syntactic error in the file.
+   *
+   * Parameters:
+   * 0: the error message from the parse error
+   */
+  static const HtmlErrorCode PARSE_ERROR =
+      const HtmlErrorCode('PARSE_ERROR', '{0}');
+
+  /**
+   * Initialize a newly created error code to have the given [name]. The message
+   * associated with the error will be created from the given [message]
+   * template. The correction associated with the error will be created from the
+   * given [correction] template.
+   */
+  const HtmlErrorCode(String name, String message, [String correction])
+      : super(name, message, correction);
+
+  @override
+  ErrorSeverity get errorSeverity => ErrorSeverity.ERROR;
+
+  @override
+  ErrorType get type => ErrorType.COMPILE_TIME_ERROR;
+}
+
+/**
  * The error codes used for warnings in HTML files. The convention for this
  * class is for the name of the error code to indicate the problem that caused
  * the error to be generated and for the error message to explain what is wrong