Force another diagnostic reporting path to be warn-only on Windows.

BUG=467287
R=thakis@chromium.org

Review URL: https://codereview.chromium.org/1095433005

Cr-Commit-Position: refs/heads/master@{#325481}

tools/clang/plugins/ChromeClassTester.cpp

@@ -95,9 +95,13 @@ void ChromeClassTester::emitWarning(SourceLocation loc,
   std::string err;
   err = "[chromium-style] ";
   err += raw_error;
+  // TODO(dcheng): Re-enable -Werror for these diagnostics on Windows once all
+  // the pre-existing warnings are cleaned up. https://crbug.com/467287
   DiagnosticIDs::Level level =
+#if !defined(LLVM_ON_WIN32)
       diagnostic().getWarningsAsErrors() ?
       DiagnosticIDs::Error :
+#endif
       DiagnosticIDs::Warning;
   unsigned id = diagnostic().getDiagnosticIDs()->getCustomDiagID(level, err);
   DiagnosticBuilder builder = diagnostic().Report(full, id);

tools/clang/plugins/FindBadConstructsConsumer.cpp

@@ -560,8 +560,8 @@ FindBadConstructsConsumer::CheckRecordForRefcountIssue(
 // -Werror.
 DiagnosticsEngine::Level FindBadConstructsConsumer::getErrorLevel() {
 #if defined(LLVM_ON_WIN32)
-  // Only warn on Windows, since there are a lot of potential pre-existing
-  // issues.
+  // TODO(dcheng): Re-enable -Werror for these diagnostics on Windows once all
+  // the pre-existing warnings are cleaned up. https://crbug.com/467287
   return DiagnosticsEngine::Warning;
 #else
   return diagnostic().getWarningsAsErrors() ? DiagnosticsEngine::Error