Add use-chromium-style-naming option to Blink GC plugin.

tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt

Index: tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt
diff --git a/tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt b/tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt
index 39d49f340eda5f3816fd9c28a0790584fa511bd5..75ca60c5231022c757b6d069106da9b33e1f8ffd 100644
--- a/tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt
+++ b/tools/clang/blink_gc_plugin/tests/fields_require_tracing.txt
@@ -1,5 +1,5 @@
 fields_require_tracing.cpp:9:1: warning: [blink-gc] Class 'PartObject' has untraced fields that require tracing.
-void PartObject::trace(Visitor* visitor) {
+void PartObject::Trace(Visitor* visitor) {
 ^
 ./fields_require_tracing.h:29:5: note: [blink-gc] Untraced field 'm_obj1' declared here:
     Member<HeapObject> m_obj1;
@@ -8,13 +8,13 @@ void PartObject::trace(Visitor* visitor) {
     Member<HeapObject> m_obj3;
     ^
 fields_require_tracing.cpp:16:1: warning: [blink-gc] Class 'PartBObject' has untraced fields that require tracing.
-void PartBObject::trace(Visitor* visitor) {
+void PartBObject::Trace(Visitor* visitor) {
 ^
 ./fields_require_tracing.h:20:5: note: [blink-gc] Untraced field 'm_set' declared here:
     HeapHashSet<PartBObject> m_set;
     ^
 fields_require_tracing.cpp:21:1: warning: [blink-gc] Class 'HeapObject' has untraced fields that require tracing.
-void HeapObject::trace(Visitor* visitor) {
+void HeapObject::Trace(Visitor* visitor) {
 ^
 ./fields_require_tracing.h:40:5: note: [blink-gc] Untraced field 'm_part' declared here:
     PartObject m_part;