blink_gc_plugin: report illegal on-heap iterators as warnings/errors.

tools/clang/blink_gc_plugin/DiagnosticsReporter.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "DiagnosticsReporter.h"
 
 using namespace clang;
 
 namespace {
 
@@ skipping 192 matching lines @@
   diag_stack_allocated_derives_gc_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kStackAllocatedDerivesGarbageCollected);
   diag_class_overrides_new_ =
       diagnostic_.getCustomDiagID(getErrorLevel(), kClassOverridesNew);
   diag_class_declares_pure_virtual_trace_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kClassDeclaresPureVirtualTrace);
   diag_left_most_base_must_be_polymorphic_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kLeftMostBaseMustBePolymorphic);
   diag_base_class_must_declare_virtual_trace_ = diagnostic_.getCustomDiagID(
       getErrorLevel(), kBaseClassMustDeclareVirtualTrace);
+  diag_iterator_to_gc_managed_collection_note_ = diagnostic_.getCustomDiagID(
+      getErrorLevel(), kIteratorToGCManagedCollectionNote);
 
   // Register note messages.
   diag_base_requires_tracing_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kBaseRequiresTracingNote);
   diag_field_requires_tracing_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kFieldRequiresTracingNote);
   diag_field_should_not_be_traced_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kFieldShouldNotBeTracedNote);
   diag_raw_ptr_to_gc_managed_class_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kRawPtrToGCManagedClassNote);
@@ skipping 26 matching lines @@
   diag_user_declared_finalizer_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kUserDeclaredFinalizerNote);
   diag_base_requires_finalization_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kBaseRequiresFinalizationNote);
   diag_field_requires_finalization_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kFieldRequiresFinalizationNote);
   diag_overridden_non_virtual_trace_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kOverriddenNonVirtualTraceNote);
   diag_manual_dispatch_method_note_ = diagnostic_.getCustomDiagID(
       DiagnosticsEngine::Note, kManualDispatchMethodNote);
-  diag_iterator_to_gc_managed_collection_note_ = diagnostic_.getCustomDiagID(
-      DiagnosticsEngine::Note, kIteratorToGCManagedCollectionNote);
 }
 
 bool DiagnosticsReporter::hasErrorOccurred() const
 {
   return diagnostic_.hasErrorOccurred();
 }
 
 DiagnosticsEngine::Level DiagnosticsReporter::getErrorLevel() const {
   return diagnostic_.getWarningsAsErrors() ? DiagnosticsEngine::Error
                                            : DiagnosticsEngine::Warning;
@@ skipping 288 matching lines @@
 void DiagnosticsReporter::NoteField(FieldDecl* field, unsigned note) {
   ReportDiagnostic(field->getLocStart(), note) << field;
 }
 
 void DiagnosticsReporter::NoteOverriddenNonVirtualTrace(
     CXXMethodDecl* overridden) {
   ReportDiagnostic(overridden->getLocStart(),
                    diag_overridden_non_virtual_trace_note_)
       << overridden;
 }