Bug 1276028 - add missing 'explicit' to ctor (r=red)

MozReview-Commit-ID: C8c4dkiGl6y

--HG--
extra : rebase_source : 8d3594dfd9f9ea340df9af50e76d18cf61dd1680

js/src/asmjs/WasmCode.h

@@ -123,7 +123,7 @@ struct ShareableBase : RefCounted<T>
 struct ShareableBytes : ShareableBase<ShareableBytes>
 {
     ShareableBytes() = default;
-    ShareableBytes(Bytes&& bytes) : bytes(Move(bytes)) {}
+    explicit ShareableBytes(Bytes&& bytes) : bytes(Move(bytes)) {}
 
     // Vector is 'final', so instead make Vector a member and add boilerplate.
     Bytes bytes;