Fix non-component Win-Clang build of headless_shell

headless/lib/headless_content_main_delegate.cc

Index: headless/lib/headless_content_main_delegate.cc
diff --git a/headless/lib/headless_content_main_delegate.cc b/headless/lib/headless_content_main_delegate.cc
index 59b6defce067d2e4f0cbd56dc893b075cce6817c..15048dbe291af70985da6c444f08d4f7af88bc3e 100644
--- a/headless/lib/headless_content_main_delegate.cc
+++ b/headless/lib/headless_content_main_delegate.cc
@@ -44,7 +44,9 @@ namespace headless {
 namespace {
 // Keep in sync with content/common/content_constants_internal.h.
 // TODO(skyostil): Add a tracing test for this.
+#if !defined(CHROME_MULTIPLE_DLL_CHILD)
 const int kTraceEventBrowserProcessSortIndex = -6;
+#endif
 
 HeadlessContentMainDelegate* g_current_headless_content_main_delegate = nullptr;