Use messages for (some) public API errors

pkg/front_end/lib/src/kernel_generator_impl.dart

Index: pkg/front_end/lib/src/kernel_generator_impl.dart
diff --git a/pkg/front_end/lib/src/kernel_generator_impl.dart b/pkg/front_end/lib/src/kernel_generator_impl.dart
index 76316455da03f9e8535a104431c16c007dc6bee5..2116a4954cab6eb2b03c28f9174b672f3953d0e6 100644
--- a/pkg/front_end/lib/src/kernel_generator_impl.dart
+++ b/pkg/front_end/lib/src/kernel_generator_impl.dart
@@ -120,7 +120,7 @@ Future<CompilerResult> generateKernelInternal(ProcessedOptions options,
         trimProgram(summaryProgram, (uri) => !excluded.contains(uri));
       }
       if (options.verify) {
-        verifyProgram(summaryProgram).forEach((e) => options.reportError('$e'));
+        verifyProgram(summaryProgram).forEach(options.reportMessage);
       }
       if (options.debugDump) {
         printProgramText(summaryProgram,
@@ -147,7 +147,7 @@ Future<CompilerResult> generateKernelInternal(ProcessedOptions options,
     }
 
     if (kernelTarget.errors.isNotEmpty) {
-      kernelTarget.errors.forEach(options.reportError);
+      kernelTarget.errors.forEach(options.deprecated_reportError);
       return null;
     }
 
@@ -156,7 +156,7 @@ Future<CompilerResult> generateKernelInternal(ProcessedOptions options,
         program: program,
         deps: kernelTarget.loader.getDependencies());
   } on deprecated_InputError catch (e) {
-    options.reportError(e.deprecated_format());
+    options.deprecated_reportError(e.deprecated_format());
     return null;
   } catch (e, t) {
     return reportCrash(e, t);