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

tools/clang/blink_gc_plugin/tests/legacy_naming/class_requires_finalization_field.txt

Index: tools/clang/blink_gc_plugin/tests/legacy_naming/class_requires_finalization_field.txt
diff --git a/tools/clang/blink_gc_plugin/tests/legacy_naming/class_requires_finalization_field.txt b/tools/clang/blink_gc_plugin/tests/legacy_naming/class_requires_finalization_field.txt
new file mode 100644
index 0000000000000000000000000000000000000000..9e37c461218723814e553aaead89ccc015334167
--- /dev/null
+++ b/tools/clang/blink_gc_plugin/tests/legacy_naming/class_requires_finalization_field.txt
@@ -0,0 +1,14 @@
+In file included from class_requires_finalization_field.cpp:5:
+./class_requires_finalization_field.h:44:1: warning: [blink-gc] Class 'NeedsFinalizer' requires finalization.
+class NeedsFinalizer : public A {
+^
+./class_requires_finalization_field.h:48:5: note: [blink-gc] Field 'm_as' requiring finalization declared here:
+    Vector<Member<A> > m_as;
+    ^
+./class_requires_finalization_field.h:53:1: warning: [blink-gc] Class 'AlsoNeedsFinalizer' requires finalization.
+class AlsoNeedsFinalizer : public A {
+^
+./class_requires_finalization_field.h:57:5: note: [blink-gc] Field 'm_bs' requiring finalization declared here:
+    HeapVector<B, 10> m_bs;
+    ^
+2 warnings generated.