Fix bug where constants were not correctly canonicalized.

lib/compiler/implementation/ssa/codegen.dart

Index: lib/compiler/implementation/ssa/codegen.dart
diff --git a/lib/compiler/implementation/ssa/codegen.dart b/lib/compiler/implementation/ssa/codegen.dart
index 8323504cd0e2c6b6bac3a9329970b46aa1a6441a..8784c2b9ffda835e34308f2dc83adf128a451fe9 100644
--- a/lib/compiler/implementation/ssa/codegen.dart
+++ b/lib/compiler/implementation/ssa/codegen.dart
@@ -1116,10 +1116,10 @@ class SsaCodeGenerator implements HVisitor {
       if (node.constant.isNum()
           && expectedPrecedence == JSPrecedence.MEMBER_PRECEDENCE) {
         buffer.add('(');
-        node.constant.writeJsCode(buffer, handler);
+        handler.writeConstant(buffer, node.constant);
         buffer.add(')');
       } else {
-        node.constant.writeJsCode(buffer, handler);
+        handler.writeConstant(buffer, node.constant);
       }
     } else {
       buffer.add(compiler.namer.CURRENT_ISOLATE);