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

tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt

Index: tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt
diff --git a/tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt b/tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt
index a05a94de8975730dab781fee5f94d98a6bad1cb4..65d62eb48fc564f180c01f3e1410089a8784c25b 100644
--- a/tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt
+++ b/tools/clang/blink_gc_plugin/tests/non_virtual_trace.txt
@@ -3,15 +3,15 @@ In file included from non_virtual_trace.cpp:5:
 class A : public GarbageCollected<A> {
 ^
 non_virtual_trace.cpp:13:1: warning: [blink-gc] Class 'C' overrides non-virtual trace of base class 'A'.
-void C::trace(Visitor* visitor)
+void C::Trace(Visitor* visitor)
 ^
 ./non_virtual_trace.h:14:5: note: [blink-gc] Non-virtual trace method declared here:
-    void trace(Visitor*);
+    void Trace(Visitor*);
     ^
 non_virtual_trace.cpp:18:1: warning: [blink-gc] Class 'D' overrides non-virtual trace of base class 'A'.
-void D::trace(Visitor* visitor)
+void D::Trace(Visitor* visitor)
 ^
 ./non_virtual_trace.h:14:5: note: [blink-gc] Non-virtual trace method declared here:
-    void trace(Visitor*);
+    void Trace(Visitor*);
     ^
 3 warnings generated.