Issue 28466. Include ErrorProcessor(s) into the AnalysisOptions signature.

pkg/analyzer/lib/source/error_processor.dart

Index: pkg/analyzer/lib/source/error_processor.dart
diff --git a/pkg/analyzer/lib/source/error_processor.dart b/pkg/analyzer/lib/source/error_processor.dart
index 3404edc49a62ad390bc01e1c536f3304282cb302..1d8d0f8479405a14b8ed961b8204136c5dfe940f 100644
--- a/pkg/analyzer/lib/source/error_processor.dart
+++ b/pkg/analyzer/lib/source/error_processor.dart
@@ -84,6 +84,9 @@ class ErrorProcessor {
   /// Create an error processor that ignores the given error by [code].
   factory ErrorProcessor.ignore(String code) => new ErrorProcessor(code);
 
+  /// The string that unique describes the processor.
+  String get description => '$code -> ${severity?.name}';
+
   /// Check if this processor applies to the given [error].
   bool appliesTo(AnalysisError error) => code == error.errorCode.name;
 
@@ -117,6 +120,9 @@ class _StrongModeTypeErrorProcessor implements ErrorProcessor {
   String get code => throw new UnsupportedError(
       "_StrongModeTypeErrorProcessor is not specific to an error code.");
 
+  @override
+  String get description => 'allStrongWarnings -> ERROR';
+
   /// In strong mode, type warnings are upgraded to errors.
   ErrorSeverity get severity => ErrorSeverity.ERROR;