rewrite_to_chrome_style: Use constexpr as backdoor to get consistency

third_party/WebKit/Source/platform/heap/TraceTraits.h

Index: third_party/WebKit/Source/platform/heap/TraceTraits.h
diff --git a/third_party/WebKit/Source/platform/heap/TraceTraits.h b/third_party/WebKit/Source/platform/heap/TraceTraits.h
index e2e31460594f8f65e41b28c5edfea579b1633e1c..49f5b511591df1f4dc123637084d5fdcb9c7320d 100644
--- a/third_party/WebKit/Source/platform/heap/TraceTraits.h
+++ b/third_party/WebKit/Source/platform/heap/TraceTraits.h
@@ -690,9 +690,9 @@ struct TraceInCollectionTrait<WeakHandlingInCollections,
     // key-value entry is leaked.  To avoid unexpected leaking, we disallow
     // this case, but if you run into this assert, please reach out to Blink
     // reviewers, and we may relax it.
-    const bool keyIsWeak =
+    constexpr bool keyIsWeak =
         Traits::KeyTraits::weakHandlingFlag == WeakHandlingInCollections;
-    const bool valueIsWeak =
+    constexpr bool valueIsWeak =
         Traits::ValueTraits::weakHandlingFlag == WeakHandlingInCollections;
     const bool keyHasStrongRefs =
         IsTraceableInCollectionTrait<typename Traits::KeyTraits>::value;